Hi Smilex, I actually have a different interpretation of the types of some of the contestants.

Troy: he is indeed an ideas man, but I also find him more practical and down-to-earth than most ENTjs. He doesn't seem to believe in theoretical knowledge and contributes to his team based on his past experiences. Moreover, his actions seem to be rather impulsive and seem to lack a sense of long term perspective. He has been described as a "loose cannonball" by Trump as well and Trump remarked that he would not trust him with multi-million businesses to handle in the long run. Even though ENTjs are generally risk-taking, they tend to take calculated risks and are effective long-term planners.

Kwame: I agree that Kwame is an ethical introvert. However, he seems to be too passive to be an ISFj or even a gamma type. Like a Fi type, he appears calm, collected, and patient. However, unlike ISFj managers, he appears rather "hands-off" and takes a "wait-and-see" approach, assuming that things will work out eventually. This is rather evident in the last episode when Omarosa made a mistake in the transportation. Instead, Troy has played a more active role to a certain extent in solving the issue. An ISFj would have been more decisive in his actions and be more eager in want to resolve an issue immediately. Moreover, his vibes and energy level seems more Si/Ne than Se/Ni.

Nick and Amy: Nick seems rather reserved in his interactions with Amy. Throughout the series, I have the impression that Amy has been "playing" with him. In the scene where they are at the bar, she seems to induce Fe and try to get a reaction out of him, bringing him out of his reserved nature. I find Nick as someone cold with a calculated mind, and I do agree with you that his style of "winning a challenge" is to thrash his opponent. As for Amy, she seems a bit "empty" to be an INTp. Remember her last challenge where she has to be interviewed by a management team? She has been described as been "irritating", "empty" and "lacking substance in her answers", basically giving answers without meaning anything.

Bill: Interesting that you think he is INFp. Why is that so? Frankly, I could not gather much about him from the show.

Sam: When I first saw him, I thought he is mentally unsound and could never be typed. From the first episode, I wanted him to be fired immediately 'cos I couldn't stand his actions and his rationale behind them. A lot of his actions are illogical, unrealistic and a waste of time.