Casualties: Unknown: Were Achievements Bugged? (Workarounds)
Short answer
Suggested fix (unconfirmed): Restart the game or check your internet connection, as achievements may be delayed.
The problem
i havent had any despite playing pretty far into the game already, mightve just been my connection to the internet or something (since i know that sometimes messes up being rewarded achievements) but maybe other people are also not getting them