For all we know the pilot banged the copilots wife.

Or he wouldn't stop farting in the cockpit.

It could be anything, but if the plan was to crash the plane, if you're already in the cockpit you just crash the plane. If the pilot never got up to leave, stab him while trying to crash the plane. It's a lot easier to crash a plane than to let autopilot do what it was already doing.

That doesn't mean the copilot might have just been a single idiot who's bad at planning. But there's just no way anyone will ever be able to trust any story on this.

But every country involved will lie anyways to maximize propaganda value. They'd be saying what they are now regardless of the truth, so even if it's actually true, we can't trust it