MIM 2016: Where are the “Ghosts” in my ExplicitMember?

I have this Dynamic Group Group1. I see the message at the bottom of the properties page saying “Dynamic group contains static members”. I open the Advanced page and look in the Manually-managed attribute, I see nothing, its completely blank. I click check in the attribute and then I click ok, it says 250 accounts with “DisplayName not known” will be removed from the the manually-managed attribute.

That should resolve the error? It does not, the error is still there. When I try amending the criteria of the group, I get Denied, saying that they group has static members.

Okay, I use PowerShell and it returns 250 ObjectIDs in the ExplicitMember field of the SG. I take one of the ObjectIDs and I search in the Portal, nothing is returned! So where are these “ghosts”??!

I go to the FIM Service MA, search in the connector space and viola! There it is, orphaned.

Run Full Import on the FIM Service to clear the orphans.