I think this episode was some brilliant editing. I think the beautiful bros talked before tribal and decided that if they figured out who wax being voted for, they would let that person play the idol. That is why Reynold so quickly and readily gave up the idol.
It is also possible that either Phillip was astoundingly brilliant, (or someone else suggested it) in that speech which spooked Malcolm.
I doubt that this is some plot Malcolm has with the favorites. He is playing both sides and trying to convince each side that his affinity with the other side is fake. He thinks it is a grand plan. I don't and I think it will cost him this game.