Hi Dan,
Not topologies or geometric networks. it's an FGDB, so no versioning. here's a screen shot of what I am working with.
For testing purposes, i copied the entire fgdb from the active production to a testing folder. I also attempted to do an export of the xml from the original fgdb and then import it into an empty fgdb. The results are the same. I also attempted on a copy of a totally random feature class, just to make sure it wasn't something specific to the fgdb. Still got the same error.
one of the things I found to trouble shoot said to check the geometry on the features, I attempted that it threw the 000229 : Cannot open <value> error.
Also gave the tools a try in ArcPro, same error messages.
It's like Arc has decided it can't see the files.