Could the initial impact have been caused by vortex ring state? Its looks like he is sinking under power and the coning extreme happens just as he is about to hit the water. Im not sure what happens to a machine when in VRS as it approaches the ground? It looks similar to the Sea king accident that happened at a UK airshow. Then the Helo hit the ground hard and the structure failed, causing tail rotor failure and destruction.
Quite agree with the movement of the CG but surely if he was moving forward the water taken on-board would have moved back-wards causing a tail down attitude! WE will never know until the investigation is complete but condolences to the Families.
Flash