2d roguelike tutorial board manager issues

Hey folks, I'm on lesson 5 of the 2d roguelike tutorial (see here) and when I play the scene after building the test game manager script I'm getting some really odd results:

You might not be able to tell, but I think it's rendering correctly as far as outer wall, inner walls, food, enemies, etc. but the spacing is so out of whack it's crazy. When I thought it was a code issue I went to the previous lesson and copy/pasted it into my boardManager file and got the exact same results. I'll post them here for reference:

Board Manager:

     using UnityEngine;
     using System;
     using System.Collections.Generic;       //Allows us to use Lists.
     using Random = UnityEngine.Random;      //Tells Random to use the Unity Engine random number generator.
     
     namespace Completed
     
     {
     
         public class BoardManager : MonoBehaviour
         {
             // Using Serializable allows us to embed a class with sub properties in the inspector.
             [Serializable]
             public class Count
             {
                 public int minimum;             //Minimum value for our Count class.
                 public int maximum;             //Maximum value for our Count class.
     
     
                 //Assignment constructor.
                 public Count (int min, int max)
                 {
                     minimum = min;
                     maximum = max;
                 }
             }
     
     
             public int columns = 8;                                         //Number of columns in our game board.
             public int rows = 8;                                            //Number of rows in our game board.
             public Count wallCount = new Count (5, 9);                      //Lower and upper limit for our random number of walls per level.
             public Count foodCount = new Count (1, 5);                      //Lower and upper limit for our random number of food items per level.
             public GameObject exit;                                         //Prefab to spawn for exit.
             public GameObject[] floorTiles;                                 //Array of floor prefabs.
             public GameObject[] wallTiles;                                  //Array of wall prefabs.
             public GameObject[] foodTiles;                                  //Array of food prefabs.
             public GameObject[] enemyTiles;                                 //Array of enemy prefabs.
             public GameObject[] outerWallTiles;                             //Array of outer tile prefabs.
     
             private Transform boardHolder;                                  //A variable to store a reference to the transform of our Board object.
             private List <Vector3> gridPositions = new List <Vector3> ();   //A list of possible locations to place tiles.
     
     
             //Clears our list gridPositions and prepares it to generate a new board.
             void InitialiseList ()
             {
                 //Clear our list gridPositions.
                 gridPositions.Clear ();
     
                 //Loop through x axis (columns).
                 for(int x = 1; x < columns-1; x++)
                 {
                     //Within each column, loop through y axis (rows).
                     for(int y = 1; y < rows-1; y++)
                     {
                         //At each index add a new Vector3 to our list with the x and y coordinates of that position.
                         gridPositions.Add (new Vector3(x, y, 0f));
                     }
                 }
             }
     
     
             //Sets up the outer walls and floor (background) of the game board.
             void BoardSetup ()
             {
                 //Instantiate Board and set boardHolder to its transform.
                 boardHolder = new GameObject ("Board").transform;
     
                 //Loop along x axis, starting from -1 (to fill corner) with floor or outerwall edge tiles.
                 for(int x = -1; x < columns + 1; x++)
                 {
                     //Loop along y axis, starting from -1 to place floor or outerwall tiles.
                     for(int y = -1; y < rows + 1; y++)
                     {
                         //Choose a random tile from our array of floor tile prefabs and prepare to instantiate it.
                         GameObject toInstantiate = floorTiles[Random.Range (0,floorTiles.Length)];
     
                         //Check if we current position is at board edge, if so choose a random outer wall prefab from our array of outer wall tiles.
                         if(x == -1 || x == columns || y == -1 || y == rows)
                             toInstantiate = outerWallTiles [Random.Range (0, outerWallTiles.Length)];
     
                         //Instantiate the GameObject instance using the prefab chosen for toInstantiate at the Vector3 corresponding to current grid position in loop, cast it to GameObject.
                         GameObject instance =
                             Instantiate (toInstantiate, new Vector3 (x, y, 0f), Quaternion.identity) as GameObject;
     
                         //Set the parent of our newly instantiated object instance to boardHolder, this is just organizational to avoid cluttering hierarchy.
                         instance.transform.SetParent (boardHolder);
                     }
                 }
             }
     
     
             //RandomPosition returns a random position from our list gridPositions.
             Vector3 RandomPosition ()
             {
                 //Declare an integer randomIndex, set it's value to a random number between 0 and the count of items in our List gridPositions.
                 int randomIndex = Random.Range (0, gridPositions.Count);
     
                 //Declare a variable of type Vector3 called randomPosition, set it's value to the entry at randomIndex from our List gridPositions.
                 Vector3 randomPosition = gridPositions[randomIndex];
     
                 //Remove the entry at randomIndex from the list so that it can't be re-used.
                 gridPositions.RemoveAt (randomIndex);
     
                 //Return the randomly selected Vector3 position.
                 return randomPosition;
             }
     
     
             //LayoutObjectAtRandom accepts an array of game objects to choose from along with a minimum and maximum range for the number of objects to create.
             void LayoutObjectAtRandom (GameObject[] tileArray, int minimum, int maximum)
             {
                 //Choose a random number of objects to instantiate within the minimum and maximum limits
                 int objectCount = Random.Range (minimum, maximum+1);
     
                 //Instantiate objects until the randomly chosen limit objectCount is reached
                 for(int i = 0; i < objectCount; i++)
                 {
                     //Choose a position for randomPosition by getting a random position from our list of available Vector3s stored in gridPosition
                     Vector3 randomPosition = RandomPosition();
     
                     //Choose a random tile from tileArray and assign it to tileChoice
                     GameObject tileChoice = tileArray[Random.Range (0, tileArray.Length)];
     
                     //Instantiate tileChoice at the position returned by RandomPosition with no change in rotation
                     Instantiate(tileChoice, randomPosition, Quaternion.identity);
                 }
             }
     
     
             //SetupScene initializes our level and calls the previous functions to lay out the game board
             public void SetupScene (int level)
             {
                 //Creates the outer walls and floor.
                 BoardSetup ();
     
                 //Reset our list of gridpositions.
                 InitialiseList ();
     
                 //Instantiate a random number of wall tiles based on minimum and maximum, at randomized positions.
                 LayoutObjectAtRandom (wallTiles, wallCount.minimum, wallCount.maximum);
     
                 //Instantiate a random number of food tiles based on minimum and maximum, at randomized positions.
                 LayoutObjectAtRandom (foodTiles, foodCount.minimum, foodCount.maximum);
     
                 //Determine number of enemies based on current level number, based on a logarithmic progression
                 int enemyCount = (int)Mathf.Log(level, 2f);
     
                 //Instantiate a random number of enemies based on minimum and maximum, at randomized positions.
                 LayoutObjectAtRandom (enemyTiles, enemyCount, enemyCount);
     
                 //Instantiate the exit tile in the upper right hand corner of our game board
                 Instantiate (exit, new Vector3 (columns - 1, rows - 1, 0f), Quaternion.identity);
             }
         }
     }

Game Manager:

 using UnityEngine;
 using System.Collections;
 
 namespace Completed
 
 {
     
     public class GameManager : MonoBehaviour {
 
         public BoardManager boardScript;
     
         private int level = 3;
     
         void Awake ()
         {
             boardScript = GetComponent<BoardManager> ();
             InitGame ();
         }
     
         void InitGame()
         {
             boardScript.SetupScene (level);
         }
 
         void Update() {
 
         }
 
 
     }
 }

Any help or guidance would be appreciated! Thanks.