Another factor to consider which again would require a knowledge of the local wind at the time is that the right turn may well have been completed to put the aircraft back into wind between winching lifts. As was stated on an earlier thread the pilot would tend to put the hover references (the mountain) on the right side (if he was flying RHS) along with the winch; with a steep cliff, it is easier to get to the overhead of the winching area that way. This would require a definite decision to operate downwind, if indeed this was the case, and a considerate pilot might elect to carry out the winching downwind, but any waiting into wind as an accurate overhead would not be required. Whether or not this was the case, it is very likely that the pilot lost good visual references during the turn (staring at the snow is not good as already mentioned) and may have moved closer than intended to the mountainside. If you introduce a downdraught to this situation, the most likely course of action for the pilot would be to try to fly his nominated escape route ie towards clear air - this manoeuvre would require a nose down attitude to accelerate the aircraft and could, if combined with a rate of descent from a downdraught, have caused the blades to strike the mountain.
The situation these guys found themselves in is every SAR pilots worst nightmare (apart from ditching at night in a big sea) and it is extremely fortunate that the whole crew were not killed.