The video indicated that just after the tap on the shoulder, there was impact showing debris coming in from the front passenger's right seat. I realise that the ascending helicopter was to the left of the descending helicopter, but the debris to the front right might indicate that the ascending helicopter had passed under and collided on the right cabin of the descending helicopter.
Approach was from the left and below and contact was made by the ascending blades on the front right of the cabin.
Reasonable ?