Here I would define the children removed from the folder, so that way you have a table to return them back. I think this is where you got stuck.
Edit:
I also wrote too fast lol. You are deleting the children with ClearAllChildren(), meaning you can’t get them back. So make sure to change their parent using a for loop, don’t delete the instances or delete the instances and create a clone that can be stored in ServerStorage.
I’m not sure how this returns the children? You can’t Get an instance or instances that don’t exist. ClearAllChildren() is simply a way of destroying (Destroy()) multiple instances
If your removing the children then they won’t be existent any more, what I would suggest is to clone all of the children in the file before removing them. Then moving these clones into the file you want.