"They" knew when he'd be coming through and "they" planted drugs in Rush's luggage. /now removing extremely tight tin-foil hat.
Well, how about this conspiracy theory? He has to pass a drug test per his probation. Can Viagra show up in a test? If so, suppose it was picked up and the info got to the right people. They see an opportunity to embarass him. Find a reason to search his bags when he returns from a trip outside the country. No prescription pain pills are found, but the embarassment is out...like they find Viagra and let that leak or someone trumps up the Viagra leak. Either way the damage is done. In this case, embarassment.
Hmmm...
Removing tin foil now.