Excellent links. There's a difference between the two routes that I think might explain how and where the poor lad met his death. This is from your first link (all trails) annotated using my worlds beating MS Paint skills ;-)
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Point A is Jays last known location.
B is the end of the good, wide track.
In the second link they went a different way. Coming up via the Carizalles mountain track (C) to the ridge forming the north side of the Baranco Juan Lopez, over the saddle (D) and back down to the end of the track we know Jay was on (B).
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I can't help but think that if I was in Jays shoes, the trail comes to an end, what would I do. If you look on Google Earth there's a building at point D. Buildings usually means access tracks. Its on the South side of the ridge so may well have been visible. There's also a faint trail visible between B and D. So it's possible, even likely, that Jay reached the end of the track and headed up rather than down. If so there's a couple of ravines/re-entrants he may have fell down, marked in blue on the following:
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As I said, academic now, the important people already know. But it will be interesting to see where the new search party the family bought in are looking, presumably for signs of foul play (not that I expect any will be found).