That one person in our entire history somehow got tested accurately (is that even possible? there isn't any sense or point for any IQ test to even go into that range, because what would you be baselining and verifying the test against?) and is advertising about it? Count me skeptical.
Someone crazy smart is far more likely to take an IQ test at some point in their life. Ask the opposite - how hard would it be to overlook the fact that a 3 year old is doing fucking calculus? That's just insane. There is virtually no chance that gets looked over.