I don't think there was any cover up involved - the verdict was pilot error all along, and the cause was simple - the pilot entered a descent of 3,300 fpm into the autopilot instead of 3.3 degrees fpa, flight path angle. The aircraft wasn't at fault, beyond the fact that it was a fairly easy trap to fall into. However, nothing actually malfunctioned and proper instrument monitoring should have picked up the very steep descent. And Air Inter were the only airline in the world NOT to have GPWS fitted to their A320s (crazy) which would also have (probably) saved them.
fly Saha Air 707s daily from Tehran's downtown Mehrabad to Mashhad, Kish Island and Ahwaz