Keep in mind that the host of a national radio or talk show is most often NOT the main party in charge of the content. Not even the producer is really in charge, it's the people ABOVE "the show," which is viewed as a package provided by the on-air performer and producer. Much of the time they get fed talking points and lines of questioning into their ear, which end up being the stilted question or biased set-up we experience when catching these shows.
Guest selection is also subject to approval by the parties above the actual show---if Medina or anybody real get on at all, it's mainly because management cleared it, and it serves their purposes towards building credibility for pushing their agenda ("see, we're fair and balanced, after all, we had Medina on, didn't we?").