The problem is that Pakistan never publishes accident investigations so the only information we are ever going to get is what can be pieced together from press reports and speculation.
What is already clear is that something went badly wrong while they were passing through a storm cell on final approach. If reports of the PF reporting loss of control by radio are true (yea right) is would seem likely that the aircraft suffered damage in the storm.
Such events are rare but they have happened in the past.