If I were a really rich guy on an island in the ocean, and I wanted to dispose of some bodies, I think I would look to the ocean rather than the land. There are ways to sink bodies so that they stay sunk.
The ocean is not that deep around there. Now, if you go about fifty miles north into the Atlantic it gets pretty deep.
The USVIs are on an old volcanic ridge that runs from Puerto Rico all the way down to the Lesser Antillies. There are still active volcanos on Monseratt. So, the USVIs and the BVIs are almost all volcanic rock surrounded by corral reefs.
Unlike Aruba off the coast of Venezuela. If you go about three miles east of that island into the Atlantic it drops to 4000 feet deep really quick. Which is why they never will find Natalie Halloway.