What is the ruling on working for a company or branch named "Zombie"?

There is no objection to working for a company named "Zombie" as long as the work itself is permissible, such as in manufacturing or technology, because what matters are the assigned tasks, not the the company's name. The company's name does not invalidate or prohibit the employment contract. The Prophet, peace and blessings be upon him, forbade naming grapes "Al-Karm" (the noble one), and this prohibition was for the sake of good manners and dislike, not for prohibition.