We were in the same boat you are. We also tried to book with Gone Caribe, but they were full. We took bup1224's recommendation to contact Tyrone at Afro Guide Curacao. We had the most amazing day with him on December 2nd of 2022. He took us to swim with turtles in the morning at Playa Piskado/Playa Grandi, what a great experience. Tyrone is very proud of his home island, and we stopped at a few great spots to see flamingos and incredible beach views. The highlight for us was spending a few hours wading in the water and hanging out at Playa Cas Abao, it was truly paradise. Having Tyrone as our private guide was great, it really felt like we were being shown around the island by a friend. I can't recommend him highly enough!