Well done in your painting; however, I felt that it looks more like putting the two images together was an afterthought. It's pretty clear to me that the pictures were edited together in post and the excess was removed with a digital soft round brush. I would have loved to see a bit more of an incorporation of the block-out style blending into the more realistic one, and vice versa.
Something that kind of bothers me about the traditional-style one is that his hands are sort-of phasing into his face and the nose is of a different proportion and shape to the nose on the other side.

Overall it's a nice departure from the standard of "person facing forward with half their face in a different style".

This is a winning piece!

Really well done