I think O’Reilly realizes a fledgling network like OAN can’t pay him what he was making at Fox. But at the same time, he’s not going to sign on for a low, seven-figure salary. Between his Fox earnings (currently collecting a $25 million buyout) and what he makes from his books and production company, he has more than enough to live comfortably for the rest of his life.
One option for OAN in signing O’Reilly and Hannity would be a deal similar to the radio contracts signed by Rush Limbaugh and other top hosts. Rush’s current deal is almost entirely incentive based. What he makes is determined by ratings and advertising revenue. OAN could also offer them an equity stake in the network, though I doubt Charles Herring would be willing to go that far.
I knew someone who had her own radio program. She rented the time slot from the station for a fixed amount, found her own advertisers, and kept the revenue. The difference between her ad revenue and her time slot rental was her profit (or loss).