Looks like from the direction the dust blows after the near miss, the wind was blowing away from the camera and the helicopter looked like he was turning into wind but instead turns crosswind with what looks like a "slipping" turn, It looks like a case of Incipient Vortex ring or settling with power which would semi dissipate as the helicopter closed with the ground but the rate of decent has grown too much for the power required.
The Coning angles on the rotor show that there was a huge amount of power but it would have been interesting to see what engine/transmission limits had be well and truly busted by the recovery.
My interpretaion but happy to learn fom any other ideas.
