Mental concerns
Alvarenga had been in a boat, in the middle of the ocean, all alone for a year, and his mental state had obviously suffered for it. When the couple on Tile Island had first spotted him, he had appeared half-crazed, and this really wasn’t surprising after all that he had gone through.
It was going to take a long time for Alvarenga to work through what had happened to him, and there were bound to be long-term issues that resulted from the ordeal. Not least was the guilt that he felt for surviving while Cordoba had succumbed to the harsh conditions of the ocean.