C# Problem Creating List of Texture2Ds

Hi everyone. I'm trying to create a generic list of texture2Ds using the function AssetPreview.GetAssetPreview to create the images. Ive checked this function to see if it properly returns a preview of an asset, which it does, but when i try to use it in a foreach loop, it starts acting up. It populates the the list, but leaves many of the slots with blank images. And everytime i generate the list, different slot are left blank.

Any help would be greatly appreciated, I've been trying to find a solution for ever d:

Heres the code btw.

Create a list of prefabs:

     public static void PrefabListCreator(){
 
         PrefabList.Clear();
         DirectoryInfo PrefabDi = new DirectoryInfo(PrefabPath);
         FileInfo[] PrefabFi = PrefabDi.GetFiles(); //Array Of Files At Directory
         
         foreach(FileInfo Fi in PrefabFi){ //For Each File In Array Of files
 
             GameObject newgameobject = (GameObject)AssetDatabase.LoadAssetAtPath(PrefabPath + "/" + Fi.Name,typeof (GameObject)); // Create new Game Object, Equals File Fi From Array
 
             if(Fi.Name.Contains(".meta")){ //Skip Meta Files
                 
             }
             else{
 
                 PrefabList.Add(newgameobject); // Add Object To PrefabList
             }
  
         }
 
         PrefabPreviewListCreator(); // Fires the function below
     }

Create a list of assetpreviews using the prefab list:

     public static void PrefabPreviewListCreator(){
 
         PrefabPreviews.Clear(); //Clears the list were using to start from scratch
 
         foreach(GameObject GO in PrefabList){ // for each game object in the prefab list
 
             Texture2D assetPreview = AssetPreview.GetAssetPreview(GO); //create asset preview
             PrefabPreviews.Add(assetPreview); //add preview to list
             Debug.Log(GO.name + " " + "was added to previews, index -" + " " );
             
         }

     }

I then just plug the asset preview list into the function GUI.SelectionGrid to create the grid of images.