It sounds like you tried everything I was going to recommend.
The last two releases of Android (11 & 12) have limited the way apps access external storage. I am reworking Sailforms to support this
since I cannot upload an Update until I support Android 11.
Running Sailforms on the emulator and backing up a group or form should give you the sailforms directory to find.
Can you reload the backup you did from the emulator? If you can, then that will help.
The emulator may be keeping its own file storage. You could try going to the emulator settings and see what it says about storage.
Connect a USB Cable to the PC with another PC and see if you can get access to the emulator's storage.
The emulator also may allow its storage to be visible to the PC.
Another thought is to see if the emulator has a file manager that might let you browse its storage.
You can also try dragging the backup.sfg file onto the emulator. It might support drag and drop.