When they did Walt's 100th Birthday celebration, WDW had holds on HUGE blocks of rooms in a lot of the deluxe resorts. They also were closing certain parks early, had entire restaurants blocked off. CRO didn't know about it, the concierge staff didn't understand what was going on as far as the restaurants were concerned. Finally I asked a friend who works for event productions in Epcot and he clued me in.
They did release rooms from the blocks as time went on and they didn't need them all. Just keep trying.
Anne