That doesn't seem like a major life decision. Maybe it is -- maybe that person will be your worst enemy or best friend...
If you act on that feeling, which is to shun the presumed shit head, then you'll never know. That's true. We're not talking about Jung's intuition here -- I understand that. Certainly there's some overlap, but I don't think that the intuition you're describing is constrained by N functions. Sounds like there's a good bit of F in there and maybe something I can't identify because of the glare of the typology reference.
Anyway, you didn't say anything about action. Just... assumptions. That all remains in your head though. Or is that the kind of major decision you meant?