GOSH There would be so much sad but Dusk would force himself to. Power through it and try to work things out with the new team. SHOW THEM HOW THINGS WERE DONE while trying to accommodate the fact that they're not his old team! Would definitely be holding himself at a distance though and spent a lot more time either with Konatsu or talking with Dawn. Further reactions would depend on what the new team is like.

HOW'S YOUR DRAGON DOING.