This is tragic, really. I hadn't heard this story until now. And I'm with Mnbruce: the people that spotted the stranded boat didn't follow up on their crew notification for 3 days? Based on this short article, my vote would probably go towards a terrible miscommunication.
Jeff Gilligan, one of the cruise ship passengers who said he saw the stranded fisherman and alerted the cruise ship's crew, told CNN last month that he took a picture of the fishing boat from about two miles away.
But a boat lost at sea is spotted by a guy named Gilligan?!