if you have any questions or suggesstions or questions please ask in the comments.
This is an story related achievement.
You will unlock this by completing Interval 06 "bridge"
if you are stuck you can watch the walkthrough i have included.
*please note it might contain spoilers.
i have read that some people didn't get this achievement after completing the mission, i can not confirm that its glitched but the only solution i found in case you don't get it is to replay the mission.
if anyone gets this problem, please tell me in the comments on how it happened (coop or not, difficulty etc) and how you solved it (if you did) so i can update the guide.