Video shows widely separated smaller pieces of wreckage (including the cockpit section, the largest piece) with individual impact marks in the snow, looks like an in-flight breakup. No sign of the main fuselage / wings / engines in the vicinity of the cockpit.
Edit:
Only saw the post re the possible mid-air after posting, it adds up. The cockpit section does look like it was sliced up by the heli rotor blades, hard to imagine other failure modes that neatly shears out a horizontal slice. The source is quoted as Interfax, the official news agency so looks plausible.