alt Hacker NewsAbout 300 survivors of different fate, according to this Spanish source (you can probably ai translate, there is a survivors section): https://www.armadainvencible.org/desastre-la-playa-streedagh...
The short of it is that only 5 can be said for certain to have returned, plus one person that stayed in Ireland under the service of Hugh O’Neill.
The idea seems to be Catholic Irish nobility "such as the O’Rourke or the Mc Clancy" may have helped them, while the English army searched for survivors and killed those who found.
Francisco de Cuellar survived in Sligo, and escaped inland to O'Rourke's Castle where he got refuge and found 70 or so other Spanish survivors. The path he took from the shore inland is marked to this day by signposts and you can follow it yourself. Granted he didn't leave us a Strava trail but roughly speaking we know the way they went.
We know what happened to him in amazing detail because he escaped north, to the Hebrides, through Flanders, Dunkirk and eventually back to Spain where he lived out his days.
O'Rourke was executed by the English for harboring survivors
https://en.wikipedia.org/wiki/Francisco_de_Cuellar