In my limited inquiry I haven't yet seen that exact background-overlap condition, but your position that it wasn't first printed onto blank security stock and then scanned is definitely what I was thinking.
This adds a bit of oddity given that according the words of the officially released correspondence, we are given the impression that this was issued in hard copy by the HDOH. At least many people are likely to infer that, since a person was sent to "pick up" the certificate.
that digitally composited view would be strongly confirmed if there were any pixels of green security background that could be found in one of the component pieces that were clearly overlapped by something else in in one of the other component piecessuch that by hiding an upper element, we can see more green background pixels being revealed.
I just looked for this and didn't see it. It wouldn't be there unless we have the original layers. This would happen if the digital composite was flattened and the layers we see are created by Illustrator and don't correspond. (When I turn off the bkgnd layer some other elements go with it.)
This adds a bit of oddity since a person was sent to "pick up" the certificate.
Good point. That could be explained this way: HI *did* print out the digital composite. The WH scanned the printout to the PDF we have.