That is incorrect. The block does not apply to resorts controlled by the same developer. All Marriotts can exchange for any Marriott in Orlando.
The Florida club has nothing to do with trading. It allows you to reserve a week at a participating resort so a Grande Vista owner could reserve a week at Ocean Pointe without needing to use Interval. It was also a method to get around the Orlando block for owners of Grande Vista. You could reserve an Ocean Pointe week, deposit with II, and then trade into DVC. Now it is a moot point because Marriott has the best II resorts in Orlando if you can't get onsite with DVC.