In the coop missions if you enable the blackops acu mod then your acu never spawns in, this happens in every mission that I've tested it in (black day,overlord,dawn). even if your ACU doesn't spawn in thru a quantum gateway like in Black Day, your acu still will never be there. ex. in overlord your acu doesn't spawn in thru something like a quantum gate but still isn't there.
EDIT: using the current version on https://github.com/aeoncleanse/Mods/tree/develop/BlackOps