Comparing Vector 3 position to a list of vector 3 positions

I have a script that is generating random treasure locations in my scene. I am basically assigning a gameobject as the "treasure spawn zone" and anything within its bounds is a valid spawn point.

My script was working fine but I had issues where treasure were spawning too close to each other. So i have been attempting a solution and im getting some undesired results. For some reason I am having multiple treasures spawn in the exact same spot. I beleive I am comparing the list of vector3 correctly, and my debug for getting the distance is returning correct numbers. Anyone see something that Im missing?

     void CreateRandomTreasure()
 {
     //Create a loop that will instantiate X amounts of Treasure
           //Assign them to a random location based on the TreasureSpawnZone
      for(int i = 0; i < TotalTreasure; i++)
      {
              //The raycast determines the random position
              RaycastHit hit;  

              //Spawn "TotalTreasure" amounts of treasure
             if(currentTreasureAmt <= TotalTreasure) 
              {
                  //Assign a random location within the Treasure Spawn zone
                  randomX = Random.Range(r.bounds.min.x, r.bounds.max.x);
                  randomZ = Random.Range(r.bounds.min.z, r.bounds.max.z);
      if (Physics.Raycast(new Vector3(randomX, r.bounds.max.y + 5f, randomZ), -Vector3.up, out hit)) 
                 {
                     //Debug.Log(hit.point);
                     //Run another loop to check if the treasure spawn position is too 
                     //close to another treasure that has already been spawned
                     for(int t = 0; t < TreasurePositions.Count; t++)
                     {                                                               
                         if(Vector3.Distance(hit.point, TreasurePositions[t]) > 3)
                         {
                             //Spawn a treasure object on that random location
                              Instantiate(TreasurePrefab, hit.point, Quaternion.identity);
                               currentTreasureAmt += 1;
                               TreasurePositions.Add(hit.point);
                               Debug.Log(Vector3.Distance(hit.point, TreasurePositions[t]));                
                         }
                        }
                    }
              } 
      }
 }