Looking at the photos of the VS and what must have been the considerable force involved in it's separation, how could this have happened aka the reported scenario ?. All the leverage would be in the wrong direction.
It's possible the aircraft could have been somewhat tail-down & travelling backwards at time of impact - though fundamentally descending vertically..
Have you heard of a 'falling-leaf' mode.. of course you have, the body is shuttling between 2 or 3 different modes of descent, first backwards and then flipping and travelling forwards.
The HS tail & wings would have broken off too, and the fuse into parts as well either side of the centre-section probably, but of course, the VS is positively buoyant and came back up.
I agree breaking off forward is what in the US they call 'counter-intuitive'
I believe the damage to the lower rudder area might be one piece of evidence that has produced this conclusion, but not the only one. In fact , if so, this shows what an incredibly strong structure the VS is...