I am just playing the devils advocate. If there was some sudden emergency, fire in the cockpit while copilot was outside, it is possible that the pilot wouldn't

I am just playing the devils advocate. If there was some sudden emergency, fire in the cockpit while copilot was outside, it is possible that the pilot wouldn't have time to communicate before losing the ability. But if we take everything into consideration, three additional turns, direction where the plane went, exact moment when the plane lost it's transponder, ... - the most likely explanation is pilot suicide.