So we have a Document Library, and inside the Document Library, we have Document Sets, and inside the Document Sets, we have Documents. No surprise so far, I know. However, when I go into Datasheet View showing Document-level metadata and try to change the value in a field, I get the following error:

"Columns that require data are not included in this view. If you want to edit rows that are missing data in these columns, or add new rows, you must first add the required columns to the view."

However, we have confirmed that all document-level required fields are included in this view. In addition, we've tried everything explained in a ton of online resources, of which apparently I don't have enough reputation points to add here.

...But to make a long story short, absolutely nothing has worked. Any advice about where else we should even start would be extremely helpful. We're pretty much pulling our hair out over here. :(

~CR