7 hours is a long time to be looking for an airport.
In all seriousness B, they are now reporting the plane was programmed to make that hard left 12 minutes before the co pilot put in his last call to say good night.
Also the fact that they made the diversion exactly at the point of dead space between Malaysia's ATC and Vietnam's ATC is pretty damning IMO. Sure that could have been a coincidence, but you add in all the other evidence you have at this point and I think it makes it fairly obvious this was no accident.