Well I know that areas like the Off-Topic sections can't be viewed by guests, but I found that if a guest clicks a link to a topic in one of those sections, like in the latest post area, that they'd be able to view the entire section.
Not really, one could use the search to find them in the vault. Why reupload a hack when it's still in the vault? And even if it's not, it's not their work so they shouldn't upload it.
Well those are some of the older PSA's that were made long ago and are buried in all the newer topics.
Since there creators haven't been on for a long time, and it's against the rules to necropost the topics, I think that since the person added them as a colab, that it should be alright.