Too much verbiage for this medium. Next time, distill it a bit.
I suspect there is some cooking of the books going on here. What does, "...not fully vaccinated..." mean? The second shot is, in effect, a "booster," adding little to the real-time protection, but extending its effect. So someone who has had the first jab but not the second is "not fully vaccinated," but that is a distinction without a difference. The two relevant categories are "vaccinated" and "unvaccinated." If someone has had the first jab, they are in the first category. THis article considers that they are in the second.