Can't get find or get rid of embedded reference

For the life of me I can’t get rid of this embedded object. Any way to find it and get rid of it? Thanks g
garage v.1.layout (11.7 MB)

What embedded reference? There are none showing as embedded in the file when I open it.

The ones marked Missing point to files that would be on your computer.

Clicking on Purge does reduce the list slightly.