At 14:15 of the third period in the Rangers/Flyers game, Philadelphia requested a Coach's Challenge to review whether New York was off-side prior to their goal.
After reviewing all available replays and consulting with the Linesman, NHL Hockey Operations staff determined that the Rangers entered the attacking zone legally prior to the goal.

Therefore the original call stands - good goal New York Rangers.
Since the Coach's Challenge did not result in the original call being overturned, the Philadelphia Flyers forfeit their time-out.