This achievement requires you to escape on the second vehicle sent in the same game.
Play the game as normal, kill all the traitors and call in the escape vehicle. Once someone is in a escape vehicle they can initiate takeoff and a 20 second timer will begin. Once the timer ends the helicopter goes and the people in it win, but if a survivor is still outside they can call for a backup vehicle from the cabin and escape on that vehicle. This achievement wants you to do just that.
Simply: Begin game, fix power, fix helipad, be left behind, call for backup vehicle, escape, done.