In reply to FesteringSore:
Not much use to you but I have looked in the Derek Walker book Rock Climbs in the Pyrenees and that route is not listed. (This is an old Cicerone guide from 1990.)
Similarly no reference to it in The Pyrenees by Kev Reynolds ( A great book if you have not seen it giving a general overview of walking and easier climbs, published by Cicerone)
Try www.camptocamp.org there may be some info on there about it ? There are certaining some inspiring pictures of some of the routes on Vignemale which have been up loaded from people who have done the routes recently so you might be able to find an alternative that has up to date info ?
I was going to go there this summer but on route we climbed at the Aiguestortes NP which was so good we stayed there for the rest of the trip.