So I guess I will post this if no one else will.
Apparently he bought 100k worth of jewelry with 30k down. The jewelry store gave him a 70k "loan" and hasn't paid them back.
First off, he just had 30k lying around? Okay, I will ignore that. I know a little about his family's financial situation and it's not completely implausible (although unlikely).
However, the part Duke should be worried about is the loan. An improper benefit is defined by receiving a benefit any normal college student wouldn't be able to obtain. Like $70,000 line of credit, perhaps? That he hasn't paid them back I think makes it worse. Wouldn't that essentially be a 70k bonus while still in school?
And it's worth noting that he was on the 2010 National Championship team.