Yeah, I know what you mean regarding the chance of a military base allowing for that sort of misuse. Clearly, there would have to be safeguards against it, but then again, look at how Bradley Manning and Edward Snowden got around the rules and changed the global landscape with their revelations.
For me, the issue isn't so much plausibility but whether there's enough verisimilitude in a story to allow the reader to suspend his or her disbelief. We're talking zombies here, after all, so the whole scenario has much that goes against it. The novel is a work of speculative fiction, so I just tried to put enough detail into the zombie mechanism to persuade the reader that such naturalistic zombies are possible.
By the way, I've been trying to add a response to the most recent thread on Scott Bakker's blog, but Wordpress isn't letting me post it. So I'm looking for a work-around...