This will be the mission Redstone gives you after storming the Gearhead Vault. This is story related and can't be missed. A few things to note for those having trouble, these are Gearheads, tougher than Bandits and have about as much armor as the Authority. Much like the Shrouded, they have their own heavy armored personnel, a Jet (name from the card). Advanced Wingsticks are very handy against these Russians along with armored piercing ammo.
Note: There is a card here, Gearhead Boss card. After playing around with the traps and using them on the Gearheads, the door behind you will open. If you go straight, the door to leave is right there. But don't leave, to the left of the door is a set of stairs. Go up the stairs and on the right should be the card.