$80 million a year for working 3 days a week with several vacations, who would quit a gig like that, even if your sugardaddy cashed-out all his millions in stock options?
If Howard was smart, he'd make a deal with John Malone of Liberty to buy-up all his shares to enable Liberty to get to the magic 50% majority ownership that they need, and maybe even give him a golden parachute for following Melvin out the door.
Howard can play TV talent show judge (AGT) and get his ego trip that he needs with that much better than being on the radio - instant feedback and instant gratification.