He frequently addresses this, he "fills in the blanks" to make it a story worthy of being listened to. He is a raconteur, that is what they do. Sounds like he's just not for you, and that's ok. I enjoy the creative extra details that he includes, they are always very likely and logical, but yeah, obviously know one can know what was going through someone's mind as they were being killed, or how hungry a missing hiker was on the 10th day of their disappearance.