My son must have wrestled the same boy. Last year a boy did pretty much the same stuff to my son and I would get so mad. But just keep telling your son/daughter to hang in there. I would like to see referee's watch for this kind of activity a lot closer but there is so much going on and the matches move so quick that these types of things are often overlooked. The boy I am referencing even did it at state and you would think he would have gotten caught there.
Good Luck and remember that those kind of wrestlers make up only a small percentage.