M'Kay here is how to get out of them map on the german side of the map by the balcony (or how ever you spell it ><) by the double barrel shotgun.

1st person: lay down under the window closest to the double barrel shotgun

2nd person: jump onto op the 1st person untill you can stand on him/her without falling off

1st person: crouch once the 2nd person is ontop of you then move away from the wall after a second

2nd: once the 1st person is away from the wall you should hover on top of the window this is when you lay down (may take a little wiggleing) then down your self via grenade (make sure you dont fall down)

1st person: try to push the 2nd person as far into the bricked up window as possible then revive the 2nd person

2nd: you should slide through the wall like your going down a slide into a desk on the other side (if you dont get through person you must kill your self again

and then the 2nd person is inside of a little nazi zombie coffee house were zombies spawn inside of that room aslong as the 2nd person is behind the desk zombies should ignore him or/and her

you will notice a small espresso machine next too you i think something is up with that thing like it is possesed or something IDK but beware

good luck i have to go on a 2 week cross country trip tomorow so i will be on a little bit to show people but VERY little