Thanks for your info.
Though according to website t4t35 it all is correct.
In fact there seemingly are two sites in this area:
1) this sitepage: Dolmen de Pierre-à-la-Fade (Rosnay commune)
2) Dolmen de Sablons is approx. 700m to the West and indeed located in commune de Doaudic. We already have a site page Dolmen de Sablons site page for it.
Something is not right. This message is just to keep things from messing up down the road