OK, maybe he hadn't seen that the ball wasn't moving but he hadn't seen that it was moving or he would have blown his whistle. If he hasn't seen it moving he can't disallow the goal so all the VAR is doing is re-refereeing something fairly trivial and sucking the life out of the game
Yes, but the referee had already decided that the ball wasn't moving so all that VAR did was to stop the celebration, waste a bit of time and then start the celebration again. It took alot of the fun and spontaneity out of the goal and added nothing.