My bet is that Mr. Nobody and the Piano Man are going to prove to be one and the same. Just out of curiosity, I juxtaposed two pictures of them, both with blonde hair, to compare and while the noses are quite different, the eyes and mouth appear to be a match.

Mr Nobody is fluent in both French and English, as well as having some German and Latin, so having some talent regarding piano wouldn't be out of the question.