There's always a good reason, an ulterior motive, an exception, a conspiracy theory, allowing for the justification of bad behavior by those who have a high profile and prominent "ministry". Falwell has invited at least two Mormons and an immoral adulterer to address the entire student body at Liberty from a right-wing political perspective in a mandatory attendance venue. So along comes a group and a leader that make the claim of taking the words of Jesus literally and seriously, certainly more theologically centered than the Mormons, and in total moral contrast to Trump-style immorality, and holds a two day revival in Lynchburg built around a Biblically-centered message, not hijacked by right wing politics, and not connected to Thomas Road or Liberty, and got a lot of attention, including from a good sized segment of the Liberty student body. I'm sure that caused some consternation on Liberty Mountain, and irked the powers that be.
So what do you do when a group of Christians with plenty of credibility and a following, even among the students at your school, come to town for a revival and the leader suggests that you get together to pray? You threaten to have him arrested if he steps foot on your campus, where you've allowed a couple of heretics and an adulterer to speak to your students. You can make all of the excuses and point the finger at all the conspiracy theories and ulterior motives you want, a duck is still a duck. And I can't help thinking how much that scenario sounds like the triumphal entry narrative.
How much different would the headlines, and perceptions, be if Falwell Jr. had accepted the invitation, prayed with the guy, and then let him address the students in convocation?