Soliciting extra benefits violates NCAA rules. There seems to be demonstrable proof that Cecil Newton tried to extort a six-figure payment from Mississippi State. That act would make Cam Newton ineligible. The NCAA cannot act until it completes its investigation, but Auburn should suspend him preemptively.
The NCAA can’t vacate Auburn’s wins until a Committee on Infractions hearing after the season. Auburn would have to vacate the wins themselves for it to happen earlier. The common perception is that Auburn has “nothing to lose” by playing Newton, but that’s not necessarily true.