Hi, I don't know if you have resolved this yet, but I had the same ish problem myself for a mo.
If it's feasible for your friend to try, this may help. On her dads ps3, login as her, and if possible still, play that game, and then exit game, synchronize her trophies on the PSN, then connect dads ps3 to hers and transfer all files across. making a image of her dads ps3 on hers. then login as she would on her dads ps3, but this time on her ps3,then goto the PSN and synchronize trophies, then if she wishes she can remove all dads old stuff if not needed. Then, If she has a spare drive laying around, put that in dads ps3, let the ps3 format it , then send, transfer her ps3 back to dads ps3 making a real backup of her ps3.
As long as dads ps3 stays working and you only put that drive in dads ps3, you have a safe full working backing of your PS3 with no 32bit drive limits. Also a nice way to upgrade your drive, if the files are to big to backup and transfer using USB.
tested works 100% from a CFW PS3 3.55 Geo > OFW ps3 3.55 Stock No reason it not working Stock to Stock PS3, as long as the firmware is the same.
NOTE: protected media will be removed from donor ps3, as its transfered.