It has nothing to do with his AF. It has to do with a 4% raiser (over a small sample I know, but pre-flop stats are much better than post-flop @ 50 hands) raising a limper in EP and then calling a re-raise. This is almost never KJ/KT/K9. At 50NL this screams JJ+/AK. Then villain minraises a c-bet from a re-raiser. How could this be AQ/KJ/KT when hero is repping AK at worst? And there's no way it's a bluff. I don't think twice about this fold.