I had not removed the "Unresolved" prefix or, iirc, touched that box at all -- as mentioned in the title, I had to delete and replace "Unresolved" in order to post the thread.
It gave me an error message about needing a "prefix" and I had to guess at what it meant. If this goes through the first time I'll edit.
e: it did go through the first time! Not sure what's going on then
Summary: I'm a Khuzait vassal at war with the Southern Empire, who have sent us an emissary asking for tribute in exchange for peace. In the decision screen, I can vote for peace, to keep fighting, or to abstain, and spend influence on the first two options. In this case everyone wants to keep...