I would recommend focusing on why you want to go to that school. Make a case for why you and the school are a good match for each other: what features you love about the school and why you belong there (curriculum, location, EC opportunities, etc.)
Most schools would rather give a spot to a waitlistee that really wants to be there then someone who hasn't shown interest. Meeting with the Dean shows interest, so now you just need to follow up on that in person.
I hope the meeting goes well for you. 🙂