There is another point.
Why would a captain or first officer run the risk of getting caught with a bomb in his possession by airport security when he does not need a bomb.
This was done by someone who had no ability to directly control the aircraft.
Pilots know well how easy it is to crash an airplane.
I spent many years trying to prevent crashing!
A little slow and short on landing....dip a wing during the flare...hot and fast landings too far down the runway...set the altitude hold on the wrong number...takeoff on the wrong tank...there must be a hundred ways to crash without risking getting caught with a bomb.
Yes, a pilot can crash a plane without a bomb.
But there was a bomb on board this one. The fireball was seen by many. The belongings all have holes blown in them and are very jagged.