May I point out that MOD wrote and published "the Rules". They are not guidelines - they are definitive/absolute/peremptory.
The Pilots signed as having read and understood the Orders and Instructions in the Flying Order Book/ GASO's/STCASI's and JSP 318 every month.
Disobeying/ignoring Orders and Instructions are disciplinary offences in the Military at any time. Doing so on Active Service raises the seriousness of the offence to another level. When such offences result in needless Fatalities they are viewed with extreme gravity.
You will recall that the Reviewing Officers deemed the Pilots to be negligent before the "Waypoint Change" (0.95 NM from impact) - when even the HOL Committee admitted the Pilots were in control of the aircraft.
Even if there was an emergency after waypoint change (for which there is no evidence) that does not alter the liability of the Pilots because they had already failed in their duty.