A possible problem of course occurring if the Pilot/s were IMC rated but had been mistakenly given a vector/radial and altitude/FL that took them into that hillside. If this was the case it will be on the radio tapes.
I was in Saudi when a PIA coming out of Jeddah en-route Karachi had a galley fire shortly after departure. A collegue was in the air at the time and from what he told me it seems the PIA crew asked for and was given an emergency descent to 4,000’ and return to Jeddah.
On the return the fire and smoke were such that the crew asked if there was a closer airport. There was, Taif, but apparently remained at their descent altitude. The aircraft impacted high ground 30 short of Taif airport which is 4,800’.
There was confusion and an on-going emergency and it was not completely clear if the PIA was given a higher alt, or was simply allowed to proceed direct at whatever alt he was at, or the fire was such that they lost control before they got there.
The thing is in a high stress situation a vital point like an MSA can be forgotten by either pilot or controller and if in cloud/night/smoke CFIT can occur.
From the pictures of the wreckage it would appear that impact/death would have been sudden.