Determining "In Stock" From an Inventory Library by Matching SKU

I have two sheets: Inventory Library and an Order To-Do List.

I want to be able to check a box marked "In Stock" if the Inventory Library shows that the matching SKU has more than 0 in stock. I am trying to use an Index and Match Function to return the actual stock number in the Order sheet and then format the checkbox to be checked when there is appropriate stock.

Inventory Library:

Order To-Do List

Currently I've only been able to get a return of "1" despite the Inventory Library showing 4 in stock.

Any help would be appreciated!