Whenever I hear people talk about Caribbean schools, they talk about the MD schools that are run by Americans. If you attend one of these, you might not match as an IMG and you won't be able to practice in the Caribbean. But there are also Caribbean schools that grant the MBBS. They are primarily for the local people, but I'm pretty sure they have some international students. If you attend one of these and you don't match as an IMG, at least you can practice in the Caribbean and try again later.