I’m not sure what happened there, but I suspect ‘can’t get lift’ is wrong. It’s hard to see, but it almost looks as if the tail rotor’s not rotating towards the end - could be synching with the camera’s shutter, though.
I suspect after it whacked the deck, the drive mechanism was barely engaged. Maybe a sheer pin broke and friction was causing it to move instead of a positive drive. It certainly wasn't right.
That dude on the deck was nearly pureed.