Achievement bug

Unfortunately, you have to have been synced to EA servers before achievements are read so if, perchance, you did something but were not connected to the server, it would not read it as having been done.

Unfortunately, again, the only thing to do is to load a save before reaching the first camp and doing that again, and making sure that you are logged in to Origin and ONLINE, before doing so. You should hear a sort of achievement sound when you get it... ☹️