The only reference I have for the QSYS files is the link
which lists all of the files used by CL commands.
I don’t believe that the backup options/configuration are stored in a system file, however, all is not lost.
You can access backup information via some system API’s:
QEZRTBKD – Retrieve Backup Detail
QEZRTBKH – Retrieve Backup History
QEZRTBKO – Retrieve Backup Options
QEZRTBKS – Retrieve Backup Schedule
The Cleanup options/config can be retrieved into a CL program using the RTVCLNUP command.
Hope that helps
All the best