I’ll boil this down. My money is on the 27 year old Co-Pilot as having done the deed.
Assuming the plane had some sort of malfunction but was not destroyed in the initial event, is there cellphone service available in that area, or is it too remote?
It would seem to me if, for example, the pilot was intentionally trying to crash the plane, passengers would use their cellphones to call for help, or would report they were going down; or, flight attendants would make calls, as they did on 9-11...
Just a question..
I agree, the 27 year old is a wild card