Great thread, I agree with your takes mostly except for Kuzan
Kuzan is still a primary suspect. If it wasn't for this conversation with Smoker I'd have actually bought Kuzan being a fully fledged captain
He immediately rushed to Smoker's aid, hasn't really given up on his friends.
His moral compass hasn't changed, his perspective and way of life did
He outright told Smoker the best course of action for the Navy to take, he's still a sailor at heart
This isn't that clear but you can see frozen tears under his eyes, indicating he's not really happy about what he's done
Oda adding this comment makes me believe it is not simple PIS that they managed to escape
Kuzan could easily freeze them even after an hour of sailing
Since Kuzan is in the same tier of strength as Teach, and has ulterior motives that don't include being a scummy cutthroat I think he's the most likely to stab Teach in the back, or at least pack his bags and leave the crew. He's playing the game too well to be true.