Hopefully there are no disgruntled/unhappy people working in the AD's office and this was all a bad adult version of the postman game.
I.E...AD Office worker meets friend for lunch and casually comments that AD Moos came to work late as he was at a Husker event the night before. The friend jokes to the AD Office worker that maybe they partied too hard at the Husker event and he was hung over. Both laugh and note how AD Moos does like to have a beer or two. Friend, excited to gossip about close ties to AD office with his/her coworkers, changes conversation to "my AD Office worker friend says Moos showed up hung over after Husker event the night before". News flies from office to office until reporter/radio personality starts reporting the rumors.
This scenario to me would seem the most likely way this all went down. Every Husker fan that lives in Nebraska or has ties to Nebraska has a friend of a friend with "inside" news so we all know how fast info can fly. If not, then the Husker AD department is in a horrible situation if one malicious employee is free to act nefariously and make a multi-million dollar organization stop on its heals to address the rumors. I would think, and hope, that AD Moos has been around long enough to earn some goodwill with employees and they would point out these types of problems quickly.
My 2-cents and a box of rocks.