I would flip it, and look at it from the other end. Have you ever had to deal with ignorant people and thought "I'm glad they can't see how things really are"? Put it in the context of the vaccination issue you discuss all the time. Do you feel that the world is better off with so many people ignorant of what you feel is the truth of that matter?
After all, being ignorant about a matter is often more than just option A or option B. And even the seemingly safe option isn't always that. If it turns out that the JWs are right about everything (impossible as that may be), then you won't be saved because you straddled the fence (lack of faith) and consorted with apostates (guaranteed DF, and you get on Jehovah's "you gonna die" list). If it turns out that they're just another religion that got it wrong, you have an endless choice of religions, most of which are probably also wrong. Makes god seem like a bit of a sadist.