I doubt there are many pilots here who have high altitude/mountain experience in a helicopter....
and even fewer with unaided night mountains experience.........
Night mountains is not for the unprepared - even with NVG - for unaided flying it is a place for twin-engine, twin pilot, IFR capable aircraft with a lot of careful planning and currency/recency on type and in the location.
Another example of self-belief in ones abilities not matching the reality of a hostile environment??? Very sad waste of life.