"Check any HSE publication and they consider any fall over 2 meters to be a risk of a fatality let alone without been involved in a serious helicopter crash prior to a fall, if that's what happened!"
There was a circular around 6 months ago to airport ground staff after an unfortunate fatal accident at another airport where a member of ground crew fell 4 feet from the side ladder of an aircraft catering truck, hit their head and died.
In relation to this incident I put more faith in one of my Scottish colleagues who was in Glasgow and was driving past and had her window down when it happened than the account of the Sun Editor who just 'happened' to see the entire incident from the roof of a multi-storey car park in the dark of night despite there being other buildings that would block their sight lines for crucial parts of the incident.
She states that she saw and heard absolutely nothing until a sudden SINGLE very loud bang which she likened to an explosion when the helicopter impacted. I would expect that if autorotation had been attempted then she would have heard something (especially being as she is from an aviation background and uses frequent heli-ferries). Her account also fits with the images of main rotor blades being craned out almost fully intact.