You mention timeshift, did you restore to the working snapshot after selecting it in grub, then reboot AGAIN?
Booting a snapshot, does not restore from it. When booting a snapshot from grub, you need to open timeshift, restore the snapshot, then boot up a second time (this time without selecting it in grub).
Otherwise, you didn’t really restore it, you just booted into it, and if you re-attempted the broken update, messed the snapshot up, too (leaving you with no working snapshot to go back to).
I’d take a backup, first, and then just send it. Then, if that doesn’t work out, do it the hard and slow way.