If JB had taken a single shot...they would have given it to him. Refs won't pull the trigger on helping when collar tie hand grab push is your offense. Burroughs didn't take any shots in that second period either (that I can remember...I was a bit on the edge of my seat watching that match.)
Edit: I forgot they also gave JB some breaks on those two challenges. Not saying those were the wrong calls, but they have to be called consistently, and based on what they did for JB in the first period, I think they did the right thing by nolf in the 2nd.