My situation is similar. I got the European Sampler on 30 December 2008, and reserved the rooms on 15 April 2009 for stays in September 2009. I called the Platinum number, and the CSR booked the reservations with no problem. She even made sure the proper notation was made so they knew I was using the ES certificates and didn't automatically order award certificates for the reservations.

No muss, no fuss.

craz, it looks as though your friend got bad info. If he's elite with Marriott Rewards, suggest that he use that phone number, otherwise he should call Marriott Reservations (800-899-7235 works for me) and hope he gets someone knowledgeable.