So, there are two islands named ‘Mas a Tierra’ - one off the coast of Chile and the other off the Caribbean coast of Central America?
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No, just the one off Chile. The Miskito Indians were native to the Caribbean. One Miskito Indian named Will, originally from the Caribbean, was a crewman on a British privateer. When the privateer visited Mas a Tierra off the Coast of Chile, Will went ashore. At the approach of a hostile Spanish ship, the crew of the privateer set sail hastily, leaving only Will behind. He was rescued by another British privateer about 3 years later. Alexander Selkirk was marooned on the same island about 20 years later. The island was a frequent stopover for British privateers since it afforded fresh meat and water and a good place to haul out ships for repair with less risk of discovery by the Spanish than almost anywhere else around.