I think you can book any of the WDW resorts that happen to fit your cruise dates through DCL, and apply remaining FCC to that booking. You’ll have to call to determine options and pricing, of course.
When I called DCL last week to add a hotel stay they said they only had the Grand Floridian available at WDW. The other two options were the Hyatt at MCO and a hotel in Cape Canaveral. But I wasn’t specifically asking about using the FCC credit.
Most of the Disney hotels (at all levels) can be booked via DCL, but it's subject to availability. And what is available to DCL via their allotted number of bookable rooms is different from what is available to the general public via the WDW website. The airport Hyatt can also be booked via DCL, and so can a hotel (whose name I don't recall) near Port Canaveral.
Book early to secure a room when it's still available. You can book multiple pre and/or post nights via DCL. And you can cancel & be refunded even after PIF.
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