I really am having a hard time with the "Faith on the March" hurdle. It seems like vaccinations, although the Witnesses made it a "Scriptural" requirement, they were probably not too big on enforcement... It seems like the dozens of extremely biased and negative articles were enough to make most reject them, without the Scriptural big stick...
Maybe that's how McMillan got away with going against official WT policy.
Another theory I have uses Occam's Razor: McMillan was a revisionist.
Yet another theory is that McMillan knew about Bethelite policy and the poor people in jail were not aware that WT officials who travelled had to be vaccinated.
(Maybe I should place the quote from McMillan's book so you know what I am talking about)