That Mi-2+ went down not because of icing, but terrible weather in mid flight to the casualty (no pick up performed). Pilot, and paramedic died in crash, doctor survived, called for help, and after an hour of search for the wreckage was transported in heavy condition to hospital.
At takeoff site weather conditions were good, and should be the same along the way. But weather suddenly changed with heavy snow fall and fog restricting visibility, as for today there is no proof of other causes.