It looked like Williams got up and was ready to shove whoever put his hands on him, and it turned out to be a ref. Williams extended his arms without looking and then when he saw it was a ref he eased up, but too late. I am shocked it was not a penalty at the very least. I think the ref showed too much leniency there, although I can understand him not making the call.
I'm surprised that did not get more attention on the broadcast.