I don't know if the NCAA is covering up or if they are just that incompetent. I suspect it's the latter, but they do have reasons for covering up things. A major finding against Auburn coming in the wake of the problems at USC, Ohio State, and Miami would make them and the sport look even worse. It would mean another vacated BCS title, possibly a vacated Heisman, etc.
Personally, I just think it means Auburn hid the money trail very well, and the NCAA was too incompetent to find it.
Agreed on all points. Well said.