Talk:Cult of Personality/@comment-92.27.86.250-20190523081046

If you get in to Richards room and kill / knock him out before you install the 3 emitters, you forfeit the achievement / trophy and it does not unlock, but you still complete the sidequest.

So simply completing this mission does not unlock the achievement / trophy, you have to install the 3 emitters before stopping Richard in order to unlock it.