MNmom -
When you check for reservations online, or by phone, you are checking for vacancy. You cannot, obviously, determine what occupancy rates are by doing this. It is, however, safe to assume that occupancy rates are fairly low when multiple room categories are still available at multiple hotels. I assumed occupancy is low for late August because virtually every room category is still available at GF, WL, BC, YC, and BW. If occupancy was at or near 100% - as it is in June and July for instance - then these rooms would certainly not be available.
It is only CR and Polynesian that do not have vacancies in late August ... this leads me to speculate that perhaps it is because of the renovations taking place at both hotels. But I certainly don't claim to know that for certain ... just a guess.