[greglepore]

Unless the pilot in the cockpit is awake and actively resisting entry, there are ways for the pilot outside to get in. Decompression automatically unlocks the door, so we can rule that out. Apparently there is a deadbolt.

Sad to say, but if this is true, it looks like the guy in the cockpit set a descent into terrain and then threw the deadbolt on his side of the door.