Setting Hierarchies of Instances in UI?

Hi all,

I'm new to programming, and I can't figure out why my code isn't working. I want to create an instance of a prefab, GRID, that gets created at the bottom of the UI layer (see arrows in screencap of instance). What am I missing?

I uploaded the two relevant scripts, ResetManager and HierarchyManager. ResetManager tells the next scene to destroy GRID or any of its instances, and to instantiate a new instance. Hierarchy Manager just sets the position of the instance in the hierarchy.

Thanks for your help!