I read it more as that a remote highlands PNG villager is not "innoculated" against the concept of, and is not aware of the methodologies that will be used by odd foreigners who have a well thought out plan to convert people to their specific ideology.

Like, if you're out shopping and some person starts up a weirdly friendly conversation with you that leads to a MLM sales pitch, you already know that's a thing which exists and why you're almost certainly not interested in participating even before the pitch arrives.

I see- your interpretation may be the correct one.