Cannot instantiate rotation on Prefab

Evening, all.

I am creating a 2D platformer game in which the player shoots in the direction of where the mouse is pointing at. I am trying to set the rotation of an instantiated bullet prefab in the direction of where the mouse is pointing. The bullet will correctly travel at _deltaX in the X direction, and _deltaY in the Y direction, but will NOT be instantiated in the direction that I specify.

This ShootController.cs class is attached to the Player. The Player does have their RigidBody rotations frozen though.

Any advice would be greatly appreciated!

     public class ShootController : MonoBehaviour { 
     
         public GameObject bullet;
      GameObject playerObject;
     
      //Attributes for finding the Angle of Attack
      private float _deltaX;
      private float _deltaY;
      private float _radians;
      private float _degrees;
 
  
  void Start ()
  {
  // Assigns the player position values
  playerPosX = Screen.width  * 0.5f;
  playerPosY = Screen.height * 0.5f - 50.0f;  // This is to properly align the origin
  }
  void Update ()
  {
  // When the PLAYER clicks and Shoots
  if (Input.GetMouseButtonDown(0))
  {
  _deltaX = Input.mousePosition.x - playerPosX;
  _deltaY = Input.mousePosition.y - playerPosY;
  ShootNormalShot();
  }
  }
  void ShootNormalShot(){ 
  _radians = Mathf.Atan(_deltaY/_deltaX);
  _degrees = _radians * Mathf.Rad2Deg;
  
  Vector3 angle = new Vector3(0f,0f, _degrees);
  GameObject projectile = (GameObject)GameObject.Instantiate(bullet, playerObject.transform.position, Quaternion.Euler(angle));
  projectile.GetComponent().Initialize(_deltaX, _deltaY, _normalDamage, _MaxSpeed); 
  }
 }