I asked because I know that if they have a backup, if they have a "main" file then it is decrypted and will work regardless. I was thinking that maybe Viridiann had that and mistakenly thought that it was encrypted to work on only one cartridge. So I asked which kind of backup they have.
I may have an idea, but without knowing exactly how save file decryption works, I wouldn't be able to know if it could work. Could they possibly restore the Powersaves backup to a new cartridge, then, without running Alpha Sapphire again yet, access the Homebrew Launcher via any way they can and run svdt to extract a decrypted "main" file? Or would svdt error out and be unable to read the save file since it isn't encrypted for the right cartridge?
I know the save file would be encrypted to a different cartridge, so if you started up the game, it would see it as corrupted and prompt you to erase the save data. But if svdt could read it and extract it as decrypted save file, there could be a chance of recovering it.
The idea here is to use Viridiannn's Powersaves backup, extract the private header from it, apply it to a rom of Alpha Sapphire, write the save data from the backup to the rom, then use svdt or SaveDataFiler to extract the decrypted "main" save data so that it can be injected into a newly-purchased copy of AS.