I am having the exact same issue. I told Dorian to keep things fun for the time being because I wanted to explore other romance options. The thing is: Other companions seem to think that I already am in a relationship with Dorian, as I cannot start their romance quests.
In the case of Iron Bull, I completed "Demands of the Qun" and took him with me while dragon-hunting. As it stands, I seem to have reached maximum approval, since I don't get any new approval messages when killing them. I am also pretty sure that I flirted with him whenever possible.
If this were to be fixed, would it also apply to my existing save or am I out of luck?
