Standalone Call of Duty Zombies Rumor

A tweet from Tom Henderson says a separate Call of Duty zombies game is in the works (thanks GameRant). Tom is an ongoing source of such details who has been called "credible" by no less credible source Reddit. Further support for the plausibility of his information can be inferred from the fact that his Twitter account was recently suspended for sharing Battlefield 6 information, so this comes from his new account. Here's word:
There is a separate Call of Duty zombies project in early development, that is currently not connected to any title.