I agree, get with an official and ask while demonstrating the move. IMO if the move was illegal in the officials judgment he should have stopped it in the match. I find issues like going to a kid after a match more like a coaching situation, maybe say something to the coach, but never to the kid, especially a novice kid. It is the officials job to officiate the match, not coach the kid as to legal vs. illegal moves. I know some of my officiating buddies may get upset about my view on this, but I feel pretty strongly on it.