Ok, duh! I just re-read your post where you said it was a MS CM.
I think it would be:
Disney Vacation Club
ATT: Carli D'Agostino, Member Satisfaction Manager
200 Celebration Place
Celebration, FL 34747
I'm guessing it would still go to Carli but I would send it to the main WDW address too. Also, FWIW, you might want to include your member # with the rest of your contact info.