Playing USA at war with UK for Canada, waiting for the 3.04 patch to finish, I decided to screw around and added a Liberate Country Wargoal for Scotland, then I loaded up the UK to see how they were doing. The Scotland Wargoal was initially shown on the "Show wars" tab entry for the war, but then after a week or so it mysteriously disappeared, and the USA offered me just a deal for Canada around the same time. I am wondering, if you offer someone a peace deal that does not include all your Wargoals, does that drop the unincluded Wargoals from the war? That isn't how I would expect the game to work, but it's the only explanation I can think of.