How do I know?

I refer you to this article from 2006, penned by Gregg Doyel:

Still stinging from 2005 Heisman Trophy winner Reggie Bush's collegiate dealings with agents and marketing reps, Southern California can expect more NCAA scrutiny if star basketball recruit O.J. Mayo becomes a Trojan in 2007.

Mayo, who is expected to sign with USC in the spring if not during the early signing period next month, is being mentored by a Los Angeles-area promoter whom the NCAA labeled as an agent's representative in 2000. That was the year Mayo's new mentor, Rodney Guillory, helped get two college basketball players -- including one from USC -- suspended for several games.
That's right. USC's compliance office knew all about Guillory in 2006 - they would have even been more acutely aware of his dealings, given than they had already been burned by Guillory in 2000. Oh, there's more:

 

Before Mayo signs, USC would be wise to look hard -- very hard -- at the Guillory connection. Looking the other way may have helped put USC knee-deep in the Ornstein-Bush mess; sources say Ornstein found his way onto the sideline for USC football games as a guest of Dana and David Pump, Adidas kingpins who once used Ornstein as an auctioneer for their annual fundraiser.

Connect the dots. One way or another, Ornstein met Bush and ultimately became his marketing rep. Bush signed with Adidas. The NCAA is looking into what illegal benefits, if any, Bush received from Ornstein while still at USC.

Now Mayo -- the Trojans' top basketball recruit since Paul Westphal -- is being advised by Guillory. And Guillory not only was once labeled by the NCAA as an agent's representative, but helped get a former USC player (Trepagnier) suspended.

Irony doesn't begin to describe this situation.

 

What happened? Well, USC didn't look very hard. Or - at the very least - they didn't try very hard to look. Arguing that somehow USC wasn't aware of these activities (or at the very least, should have been aware) takes a level of cognitive dissonance that's almost psychologically imbalanced.