I had a similar incident happen at Keystone 6 years ago. There was a Ski Instructor arcing GS turns back and forth all the way across the run. Not going particularly fast because he was going all the way across the hill with each turn, thus half his time was spent going sideways. I was skiing more of a fall line and as he swooped across the hill on one of his right turns, I proceeded at my faster speed to pass him on his left. He finished his turn and arced all the way back across to the left side of the run and body checked me from the side. IIRC, neither of us fell because both of us were good, but we were both pissed.
He tried to take my pass from me and I laughed at him, because the way I saw it, he was carving across an entire run without ever once checking across or up the hill to see who was coming and where he was going. I never gave him the pass. We bickered back and forth a minute, he started to get aggressive so I took off and he never caught up. I would have gladly stayed and debated it between him and the patrol, except by strange coincidence, I didn't have my own season pass that day. (I had just quit Mountain Sports Outlet and my pass was not valid, so I was on a "borrowed" pass).
The debate probably never would have been solved. By the time of the collision, we were side by side. So there was no downhill skier. Of course I had seen him, but he was on the right side of the run and I was on the left by the time I started to pass. He never looked where he was going, etc. etc.
In my case, the only two people who know how it happened are the two involved, and it's probably the same case for the camera man and the alleged "girl" whom he collided with. Had she stopped to debate it, she may have a strong case. But having taken off, it makes her look guilty.
That being said, it looks like a simple collision where both may be at fault for not paying enough attention to their surroundings. I don't think she should have to pay.