He started on the edge and then skied into the center before he got hit. If he had stayed on the side where he was standing nothing would have happened.
No problem standing on the knuckle. Problem was the kid did not look uphill before he skied into the landing. The jumper got low and was spinning so he could not see the kid anymore. He saw the kids standing there and was going to give them a show. That's awesome. The fault was the kid on the knuckle that should have looked uphill BEFORE he started again. End of story.