Having flown the aircraft in question (though not recently) I can't help wondering; why does anyone want to second guess the investigation?
A guess, is a guess, is a guess!
A theory, is a theory, is a theory!
Why not leave the speculation to the likes of Learmouth, Moody, and the rest of the sad gutter press.
ANY professional pilot worth his salt, will simply allow the investigation to take it's course!
Anyone who isn't a professional pilot, please feel free to continue your banal commentary on matters you do not comprehend!