Are any of these servers what you are looking for?

Servers with "Zombies" and "Server" in the name:
Zombies Testing - HaloPCServers.com
ZOMBIES - HaloPCServers.com
evL` ZOMBIES~- HaloPCServers.com

Servers on :
MLG
Counter-Strike: Global Offensive
A New GameServers.com CS:GO Server