Long time ago, during "chat hrs" with many students and instructors the "Golden rule" was always => If in trouble? => "Fly the airplane" => Climb, => Call => and Confess.
Only issue here could be icing that prevented the first 2 => Fly the Airplane and Climb. => Why the descend? => Will remain a mystery for ever.
If it was to stay VFR?? At night??? Over the channel? In winter?? In single engine?? With a snow front coming towards you?
Too many questions for my brain.
My money is on ice taking them down (or out of control.) But with that weather announced, they should have stayed on the ground.