That many achievements for one thing but no other map. Sounds like it would be a strike force mission. (Hey a screecher could be some sort of vehicle.) Doesn't say zombies. There's been no official word on anything zombie map related. Most "leaked info is fake/mostly fake.
My conclusion: It's fake.
My friends call me ozy XBL: ozy8080 3DS FC: 3050-7599-9169 add me and message me your FC and we can play sometime