I had a problem with my car running too rich for a while and un-burnt fuel getting sent down the exhaust. The fuel reacts with the stuff inside the cat and causes it to break apart. Did you happen to pull the code just to verify it was the cat and not something else as well? I haven't heard of exhaust gases being "too hot" to burn the cat out...of course I there is a lot of stuff I haven't heard too. Oh well, best of luck to you