Perhaps because to have done so would have obliged MoD to admit that there were critical safety of flight concerns over the Mk2 - and perhaps a case of corporate homicide would have been open to the realtives of the deceased.
I still hold the view that the appalling verdict of 'Gross Negligence' was brought to protect MoD from some very expensive claims being made against it for allowing passengers to be flown in an aircraft which Boscombe Down wouldn't even allow Test Pilots to fly....