Excel not finding Add-in

Hoping you guys and tell me what I'm missing when trying to get Excel to find the right location for an Add-in on startup. Details below:

I decided to keep an Add-in I was testing out and moved it into the Excel Add-in library under: C:\Program Files\Microsoft Office\root\Office16\Library

But now whenever I launch excel, this error pops up:
XCLERROR1.PNG

To troubleshoot, I've followed these steps:

Found the Add-in I'm looking for, and see it's displayed in the old directory...
XCLERROR2.PNG

Selected it and hit "GO" and browsed to replace it:
XCLERROR4.PNG

Tell it to update all the links:
XCLERROR5.PNG

Verified it's now pointing to the right directory:
XCLERROR6.PNG

But when I close and open excel again, none of the changes I made take. It gives me the same error, and points to the old directory.

What am I missing?

Thanks!