I think there is a connection between Bill and William Roberts. They could be the same person, but as has been pointed out, the old news clips do not use the title Dr. Could it be Father and Son? There is President Ronald Reagan. He has a son that goes by Ron Reagan. Not Junior.

What we see at Raydon can do a really good job building special zombies, what we have does not get to the root cause. Even complex chemicals are not really contagious.