I was unable to register for this promo (1st time this has happened to me). Instead of wasting time calling, I spent 2 mins submitting a support ticket on the Marriott website. Heard back through email in about 24 hrs confirming successful registration.
Promo didn't immediately show up in my account but it showed up a day or two after the email.
A good alternative for those who don't want to call in - there is also paper trail in case I don't receive the pts or nights later.