This is our favorite excursion in Belize. We booked it directly through Carnival. The boat to the island, picked us up, from the cruise ship. It is a tender port, so the excursion boat acted as a tender boat and loaded everyone directly from the ship gangway area. It was nice not to have to tender to shore & then get on another boat to the private island.
This excursion includes snorkeling & unlimited rum punch. There is a food truck on the island to purchase lunch if desired.