In my original problem with losing albums I think I tried restoring the catalog manually, not by doing a full catalog backup from within Organizer, thinking that all the data was directly within the photo files themselves or at least linked from within the photos themselves. I now realize that I was wrong in that assumption. I now realize that all the Photoshop Elements data is connected together by what appears to be a fairly simple relational datadase. Move parts of the DB and stuff falls apart.
I get it now.
Thank you. Your response made me think a bit more deeply about how the data is connected.