Eivissa,
An interesting flight following clip you posted there from Youtube.
What immediately strikes me is that the surface contact/boat that they were obviously working with until 2014 (according to the clock bottom right) can't have been very far away when the helo contact disappears (approx 2016) yet continues to head away from the scene until clip finishes at 2020. I would have thought they might have seen /heard something and come to investigate but maybe weather/engine noise/heading precluded that....or maybe they did after 2020. Just an observation.