Too much to easily condense. But start with shady dealings between Auburn's board of trustees and a bunch of shady businesses - a failed bank, a variety of gambling interests, etc.
FBI investigates the group of shady businessmen under the RICO act, gets a wiretap on the phones of one of the guys of the center of the shadiness, and for 13 months listens in on every call that went into and out of his office. They find the links to Auburn's BoT, and to Auburn's athletic boosters. Supposedly has a bunch of stuff on tape with Auburn boosters talking about which players get how much money and when - which although against NCAA rules, isn't actually criminal. But they also supposedly have all kinds of info on money laundering, tax evasion, etc - talk of players' families being paid-off in casino chips, or given ATM cards tied to accounts with no names on them. So now the FBI has a reason to be investigating these people at Auburn for CRIMINAL charges.
I must admit that the rumors flying around for the last few weeks about the FBI being involved make a lot more sense with this story as background. There's no reason for the FBI to be investigating Auburn for pay-for-play. But with money laundering, tax evasion, racketeering and other RICO charges on the table, FBI involvement makes a lot more sense.
If a fraction of this is true, Auburn will get the Death Penalty. It's not just a school with a lack of institutional control, it's a school where the control of the institution was maintained by a criminal enterprise that likes sports and wants to buy the best football team available...