Shadowrun Returns

You can buy an ID card from the janitor in the kitchen or you can fake a ruined card and talk your way into the offices to make a new one. From here you can use the card printer to make a card with access to the Inner Sanctum or make a card with access to the housing area and steal one from one of the lockers along with a uniform.

Eventually you will head to the kitchen and sneak your companions into the building, using your newly acquired card to head deeper into the facility. The achievement should pop as soon as you go through the door with the yellow icon.