Chosen Solution
When I removed the logic board I found a small rectangular piece of metal with a hole fell out with it. I can’t seem to find mention of this in any of the steps in the guide. It has the corner cut off and has a small step on it. Update (01/17/2020) this is not an answer but i wanted to add the photo as I still have not figured this out
Review Step26 in this IFIXIT guide: Mac Mini Late 2014 Power Supply Replacement. Update (01/17/2020) Duh! Thats a different clip ;-}
Thats the SATA cable hold down clip. Review Step 15 in this guide Mac mini Late 2014 Logic Board Replacement
