Do I use a title in the mention "joint with [...]" when mentioning my advisor or a coworker?
In my experience (math), I have never seen a title used on such an occasion. It's always "joint with Jane Doe and John Doe", i.e. the full name without any title. Even if it's a student jointly working with a professor.

Think about it: in a bibliography you never use any title. The goal of the mention "joint with" is the same as in a bibliography: give credit where credit is due, and let people look up who did the work. A title is unnecessary for that.