Can't restore Sudoku backup from old phone

[skorpion9]

Same problem, like issue #17, but with the Sudoku app, and without a workaround.
The apps are the same versions on both phones, but the old phone is based on Android 10, the new one is on Android 13.
I can see the different construction of the backup files, but I am not able to convert it.

The Backup app should handle it and convert whichever backup type is provided.