So. One immediate problem, from statistics alone, is that the people you are meeting with are not drawn from a random sampling of the population. There is clearly a 50% chance that one of those two unknown people is the CEO. (If it were 3 people, a 33.33% chance, 4 people a 25% chance, and so on.) So I don't think your reasoning is sound.
Also, the end result of your argument is "the black person in this group isn't likely to be the CEO because they are black," and, well. I get that you're trying to arrive there through what you think is pure mathematics, but it is nonetheless the kind of conclusion that I believe the kids call "problematic."