"Professor...?" He blinks blankly at the boy. "I don't know, I might be."

No, that isn't a flippant way of dodging the question. His title isn't mentioned on his ID, so he has no idea.

"I must be some kind of scientist or doctor, I think, but I don't know about professor." And where did he get that idea? He holds out a photo, one that has him in it, and the professor in the picture is wearing a labcoat (while the man standing before Leo is not). Well, he kept some of his cultural knowledge, at least?

"Why do you need... a professor?"