I'm not sure about using steam achievement unlocker cause I heard some achievements sites will report you or somethingIf it the game is bugged on that (which I don't know) you can force it with steam achievement unlocker (if you use steam)
Otherwise report it as bug. I haven't finished the game so I can't answer that.
I'm on PC - Steam. I sent my ticket. I don't know what else to do.I don't know what platform you are on, but you can report achievement issues here by clicking on "Contact Us":
(on the same website this article can be found for consoles as well)Welcome to CD PROJEKT RED Technical Support! Here you will find help regarding our games and services, as well as answers to frequently asked questions.support.cdprojektred.com