Sorry to hear about your trip. Yea, KSA only has maybe 3 hotels, and I know the one we were in, the Nautilus Resort, will prioritize rooms to outgoing guests.

Knowing what I know now about KSA, if I was stuck there overnight on irrops, and no hotel, I would try and get a car, and if nothing else, sleep in that. Better AC than at the airport.

Not knowing the rest of your itinerary, is changing to the eastbound Island Hopper an option for you, even in Y? Could be an opportunity to salvage the experience.