by Ken Task.
Follow up ... for completness of analysis?
A successful (complete backup) would have a moodle_backup.xml file which is a roadmap for the course contents. Not present in your directory. Also missing ... files.xml with corresponding files directory ... even in quizzes there should be some.
The very last process in backup and restore is to restore from a backup.mbz file in that directory to another (copy) course. that file is also missing.
Think you need to research some more on those snapd created directories - and how they are supposed to work.
Ok - done all I can do!
'SoS', Ken