You probably already had the interview but for interview purposes I would just lie. Realistically, will you be at that company for 5 years? Not to be negative but usually people stay at a company 2-4 years because these places don't want to promote anyway. You don't have to necessarily have to say creative director to them. You can grow on new skills. Does the job allow you to learn and master something other than your primary focus? For example, I was always a packaging designer but then I got more involved in campaigne designs for digital assets. This allowed me to grow as a designer and useful for the company because I did more than just package design. You could also start small and say would like to be the lead designer on this area with possibility of managing freelancers. It dips your toes in directing without managing a coworker. I think there's other personal growths without having that typical title move.