This has become kinda like a meme today, where everyone puts their own words to it. But truth is, Mora could've made a joke that Heupel actually thought was funny.
Maybe Mora said something like "I'm hurryin' off the field before y'all score again" or "Sorry, gotta take this call from my agent."
Pretty sure he didn't say, "I put ten thou on the over. Off to collect my retirement!"
Or maybe Mora's thinking like a basketball player: Don't want to be caught in the picture when the other team just threw down a monster dunk.