II gave more context to the first.
Dutch always was a bad man. Like John said, he got found out for what he truly was. Early in the beginning there were several instances where he blamed Arthur for everything. It was subtle and un-noticable in the first walkthrough, but thanks to some YT videos, it was very noticable in the second. He blames him for not being at the Blackwater job and for the false explosion in the Cornwall train robbery. But contrary to not noticing in the first walkthrough, I noticed in Chapter III: Clemens Cove in the mission The New South when Hosea, Arthur, and Dutch get back from fishing, Dutch says "I think I-" and then catches himself and says "WE are going to be ok." This threw me off and I was a little confused and I remember the first thing I said was "he said I, why'd he say I?" Also he makes sure he's safe before everyone else. A leader is supposed to make sure the gang is safe before himself.