(adsbygoogle = window.adsbygoogle || []).push({}); Thanks to USCTrojan for finding Solo Out of Five.
Out of the maps listed were found by me

Works For PS3, XBOX, PC

USCTrojan's Tutorial
to get under the map on solo buy quick revive 2 times. you get a crawler and zombie jump on top of quick revive the zombies can still get you get downed and buy quick revive again the machine will fly up through the ceiling and you will fall through the floor.


Out Of Map Solo Only:
Kino Der Toten - Confirmed Works
Five - Confirmed Works
Verruckt - Not Sure
Shi No Numa - Doesn't work
Der Reise - Confirmed Works


Under Der Reise:
[ame=https://www.youtube.com/watch?v=jvvX0TejYbQ]YouTube - Crazzy_Dexter407's Video[/ame]

Der Reise - Under the map was different from the other maps I didn't fall through I map to eventually my death, when the quick revive machine lifted into the air I was tuck onto a barrier as if I was in it so I started moving side to side and I fell under and got stuck shown in the bad quality video :p and for the zombies they still come but they run to the mainframe for some reason and die out.

Under Kino Der Toten
[ame=https://www.youtube.com/watch?v=Ijj9IJ_4odI]YouTube - Crazzy_Dexter407's Video.[/ame]

Better Video
[ame]https://www.youtube.com/watch?v=J45TaLjWOIU[/ame]

That's it, Thanks for your time.