I doubt it. Most accounts I've seen say that Lloyd Lake, at the time he allegedly provided the Bush family with any benefits, was being convicted for extortion. IIRC, Lake's ties to the Bush family were through another family member in the SD area, and has no ties at all to USC.
It's far more likely that the guy was just some d-bag trying to come up with a sleazy way to cash in on Bush's would-be fame. Not somebody with any ties to the university.
Now, what the punishment will be is the question. How I see it going down is Bush's family getting caught for receiving illegal benefits, while USC had no knowledge or part in it. Do you penalize USC? Do you take away the national championship?
I know most people on here are okay with that because they hate USC for no apparent reason, but I have a hard time taking it past the point of stripping Bush of individual awards and records.