To play disc put in 360 console?

I let my (dishonest, douche) friend (whom I wrongfully trusted) borrow my GTA IV and he returns it to me 6 months later in less than than average condition, its got circle scratches around it, not deep though, just to where it looks like his xbox probably gave it the scratches from playing too much, or as if it were an old used game, but still looks playable... So I bring it home in his Krash Bandikoot computer CD case because he lost my case, and I put it in my 360 and it wants to play it as a DVD on the dashboard. So I hit play and it comes up with the error message on a white screen "To play this disc, put it in an Xbox 360 console." It's not my Xbox that's the problem, it plays all my other games and movies perfectly fine, it's just this single game. I confronted him about it and he told me that it's mine and he didn't scratch it, it was like that originally and he didn't do anything to it (which is major BS because it had not a single scratch on it when I first lent it to him.) So I want to know, did he scratch it and that's the reason why it's not playing, or did he do something to it to where it wouldn't play, like try to overwrite something on to it (if that's even possible) because this game really doesn't look that messed up, just light scratches like I said...