I came here to say this. :)
They’ve got an OCEAN of water. They just need to take the salt out. This is how they do it in the oil-rich countries in the middle east.
Build two huge plants and get plenty of water.
I am not disputing what you write. In fact, I was in Aruba last year and all of their water comes from desalination.
I think the bigger issue is transport and volume. I would cost a fortune to move that water out to the place where they need it.