Doesn't sound like he's in any trouble. People touch each other in clubs. Is there always verbal consent when someone grinds onto someone else? No, you can't even talk in those venues.
She approached him in a bar, they danced, and he maybe wanted to go on with things - if he overstepped his mark she would say so, slap him, walk away etc. How many times do guys make unwanted advances on girls and they do one of the above? It happens all the time, and the guys get put in their place all the time.
It seems there's no evidence that anything else untoward took place. Her word against his. Nothing will come from that.