It looks like the stern of the boat was going up over a wave.....just as the pilot took off.
That put the helo angled and moving forward....just as the ship rocks back.
(notice there's a light and probably a tower in front)
Plus a skid might have gotten caught in the net.
Pilot quickly yanks back the cyclic stick and crashes the tail rotor.
(there is a guard ring which is ineffective)
A lucky spin and a perfect dump back to the surface ends it.
