This section of Call of Duty Cold War guide provides information about successful evacuation from the map in the Outbreak mode. Escaping will grant you more experience. This page contains a detailed description how to do it.
Every 5 rounds, starting with the 10th round, you will be able to escape from the map in Die Maschine. In a place like in the photo below, every 5 rounds, a radio will unlock (in the courtyard in front of the building). After interacting with the radio, you have to get to the helicopter quickly. You're going to land in a pond.
Notice that you can not leave the map when zombies are nearby, because they block the way for the helicopter - kill all the zombies in the pond. All it takes is for one person to get to the chopper.