Yes, I noticed that as well. I don’t think that’s rust though, I think it was salsa or pizza or spaghetti sauce. Maybe it fell off or was wiped off, but yes that a point in the other direction.
I’m fairly certain that it is rust from a cheap staple or paper clip, and that the punk version doesn’t come close to matching the right shade of rust to match it.
Also on the original picture I saw what appears to be fraying of the paper on the creases of the folds as would be found on a document that is forty five years old.
over a period of time not only does paper age yellow as we see but the paper will tend to de-laminate where it has been bent or folded. Most papers are made from bleached wood pulp (fibers) pressed into sheets and will over time separate at those points where it is stressed such as a fold.
Anyone that believes that this forgery is the same as what we were first shown has been punked, it is nothing but a not so cleaver attempt to fool the public.