I use postgres for my install and had a similar thing happen to me. I tried moving an org credential to a folder, which moved the folder to the org, and kicked all other credentials to “no folder”.
Also, this support thread points out that folders aren’t actually folders in the backend. Maybe batch moving credentials to an org breaks the connections to a folder?
GCam requires the Google Photos app to be installed to load previews.
One way to fix this without installing it is to use GCamPhotosPreview. I use it myself and it works as expected