I'm playing as England and a couple of things have come up through the course of the playthrough that I just want some clarification on.

1) During my subjugation of Scotland War, France jumped into defend. While making peace with Scotland (who is negotiating for the entire alliance), there is no option for me to demand cores back (namely from France). Why is this?

2) Later on I was in a coalition against Burgundy (who had been aggressively eating France- first time in a while I've seen BBB getting destroyed by AI). Austria and several other princes, as well as France were in the coalition, and Burgundy had Castile as an ally. Bohemia called me into a war where Austria was fighting on the other side, and while that was still going on France triggered the coalition war. I was brought into the war automatically and obviously Austria wasn't. I understand why, but I was just wondering if it's random who gets pulled into the coalition war first (i.e. could it just as easily been Austria in the war and so I would be left out?) or is there a specific mechanic that decides.

Thanks guys