Lurking 123
I'm afraid you got that wrong. A finding of gross negligence following an accident is not dependant on the cause of the accident.
If you indulge in an unauthorised low level beat up of your girlfriends house and suffer an uncontained engine failure which results in abandonment of the aircraft then you would be found negligent to a gross degree because your unauthorised actions resulted in a situation where no action on your part could prevent the loss of the aircraft. The same failure whilst complying with your authorisation would not result in such a finding.
The senior reviewing officers of the Chinook BOI concluded that the pilots were grossly negligent in that they continued to fly the aircraft directly towards the Mull at high speed, at low level and in deteriorating visibility thus failing to comply with their VFR minima.