Hmm assuming the disk isn't super scratched up, I'm thinking you need to configure the region correctly.
I think if it was a decryption error, you'd have something different to a read error on what looks like one of the first blocks.
I remember there's a cli utility for setting the region that you should be able to get from your package manager, I can't remember the name off the top of my head
Edit: reread your post, regionset rings a bell actually. If it's not available in your package manager, perhaps try building it from source