I'm pretty sure he tapped because of the pain. I can assure you that a well executed neck crank can make you tap. And if you don't tap, your jaw will most likely crack.
I was surprised not to see Ronda tap though.. She's tough!
Story wasn't being choked in any way. The crank pain alone made him tap cause he had nowhere to go. There's a sweep from the guard in BJJ where you embrace your opponent's head with the GI sleeves and twist it to one side. The pain of the crank do all the rest and you're on top again.
Liz attempt was fast and legit and Ronda had to fight for her life.
Great fight for both ladies.