Go back to the question I asked about him being adopted, and how he accepts his adopted families heritage when compared to America adopting foreign peoples. He answered with that he wasn’t black, but I think that would be good to come back to and have him elaborate on.
Also have him elaborate on any buzzwords or typical characteristic that are associated with nationalism that he uses or says he is.
Remember how the fury tried to drive home that he was straight, like that was going to save him and make us instantly accept him. Look for signs like that.
I tried to thinks up more and honestly the guys seems fairly genuine. Just get him talking and keep him talking. Get to know him better and if he slips up so be it.