The video does seem to show that the helicopter had quite a bit of forward momentum at the time of impact, so one can safely assume that it wasn’t hovering as was initially reported. For the rest, I must confess my knowledge of helicopter maneuvering is so close to zero so I can’t comment on the event!

He should have known better, and this is clearly a case of pilot error, not knowing his machine well enough to properly fly it. When you showboat in a helicopter, and don’t know what you’re doing, it will come back to bite you.