The S-Bahn Köln S19 line is using DB BR423 trains instead BR422 trains in reality. That's why I decade to suggest the BR423 in S-Bahn Köln livery. The DB BR423 which is included in München-Augsburg has GTO sounds, so this one would have IGBT sounds.
Someone here posted a video of the Düren station last week and you could hear a 423 depart with the GTO sounds as well. I would still love to see the 423 over the 422 on SKA, but I doubt it will happen. Interior and livery don't really match...