We mere mortals probably don't have the wherewithall to read disks in this state but I would try other machines and software before giving up.
If it was really important to you there are people like Vogon who can read corrupt media for a price. I doubt they'd charge very much for this but don't hold me to it!
On a lighter note, why not take it (them) to the local cop-shop and tell them that you that you think that there are a lot of "adult" images recorded. They'd be glad to help out, I'm sure.
