1- The kid sounded adverse to dressing up on a daily basis. If that is the case, NYC finance is the last place for him.
2- Many Mormon kids are taught from when they are young that Missions will be a great help to them in their careers afterwords. They will learn self discipline, goal setting, communication skills etc. Sounds like this kid took it a bit too far but it sounds to me that it is more because he was trying too hard than anything.
3- If he couldn't handle your interview, he doesn't belong in NYC. Sounds like he didn't shy away from your comments but he could have listened a bit more to what you were trying to tell him.