Not a problem. A simple dual-key solution will suffice. Pre-place the anthrax in undisclosed locations and e-mail the martyrdom boys the locations, locker combinations, etc. when the time comes. These martyrdom boys are attack dogs straining at the leash. When the time comes, they won't need persuading. From Saddam's point of view, this al-Qaeda partnership thing is absolutely golden.
Building a doomsday deterrent using low-tech pieces like al-Qaeda wackos and aerosolized anthrax isn't that different from building one based on ICBMs and thermonuclear bombs. The control problems are pretty similar, and as readily solved.