Spawn a power up after asteroid death

So I am making an asteroids clone to get used to Unity. I have the Asteroids spawning and such and destroying via my bullets from the ship and a GUI that updates the score/lives as well as a shield power up(that has 2 uses per pickup).

I made a PowerUpSpawner to hold the shield and any future powerups I make.

public class PowerUpManagerBehaviour : MonoBehaviour 
{
	
	public List<GameObject> PowerUps = new List<GameObject>();
  	
	public void SpawnPowerUp(Vector3 position)
{
	var powerUp = Random.Range(0,PowerUps.Count);
	var randomAngle = Random.Range(0,360);
	
	PU = PowerUps[powerUp];
	Instantiate(PU,position, Quaternion.AngleAxis(randomAngle,Vector3.up));	
}
}

Now what I want to do is call the SpawnPowerUp and get a GameObject back in my AsteroidsBehaviour like this.

    	void OnTriggerEnter(Collider colliderObject)
    	{
    		if(colliderObject.transform.tag.Equals("Bullet"))
    		{
    			Destroy(gameObject);
    			Instantiate(AsteroidExplosion,transform.position,transform.rotation);
    			
    			//Access powerupspawner and spawn a power up.
    			var PUMB = GameObject.Find("PowerUpSpawner");
PUMB.GetComponent().SpawnPowerUp(transform.position);

    		}
    	}
    }

Now even though it seems like it should spawn the powerUp (a random one via the Spawnpowerup) when the asteroid dies, it doesn’t do anything. I have my shield two times in my PowerUpSpawner GameObject in the scene so I’m not sure why it’s not spawning at all…

Any help would be really appreciated.

EDIT:
Cleaned up the code for the non important and empty methods etc.

I personally made an asteroids style game, called asteroid buster, but anyway how i handled power ups was to generate a random number and then have certain ranges select a certain power up. Like that way i could have certain ones more likely than others to get spawned. So when you do on Collision enter, generate a number, then spawn a prefab for your powerup based on that number, then destroy the asteroid afterwards. Hope this helps!