Shanty.org most emphatically does not think it is Caribbean. The article merely states: "One conjecture, voiced on the Mudcat Cafe website in February 2000 by a guest posting as Chris, was as follows: ...". Having then quoted the Mudcat posting, the Shanty.org article concludes with the following:

In over twelve years since then, nobody has produced any evidence to either support or refute these conjectures: in fact nobody has even stated whether or not they agree with them. As the old shantymen said "They thought the moon was made of cheese, Oh yes, oh, And you can believe it, if you please, A hundred years ago"