Here is my "All in One" Guide for the newest Spec Op Mission.
You can earn all Achievements in One Run, the only Difficulty are the 2 Dogs which cost the Flyswatter Achievement.
For the Juggernaut use the Crate at the Middle of the Plattform and circle around with the Juggernaut. Easy Going, ammo and Weapons are enough here.
Question? ask me :)