Somewhere else on FR it was explained that the archive shows how many times the site has been viewed not necessarily how many times it was changed. There is a notice on the archive page that explains this too.
But yeah the page is a plant probably done by the killer to distract from his true motives and beliefs.
Yes, you are correct. There is supposed to be an indicator on the archive's "table of contents" that indicates whether the page has changed since the previous snapshot. But, I've found that it isn't accurate.
You can look at the archive's collection for Free Republic forum index page (not the home page). It has nearly 1,400 snapshots since 2008, but in a quick spot-check, I couldn't find any that were marked as "changed". But, if you look at two adjacent snapshots, they have clearly changed.
However, I did a quick comparison of the last two snapshots of the fake profile, and couldn't find any changes. It's not easy to compare them, because there is a lot of metadata in the page that is modified by the Wayback machine to maintain the integrity of multiple copies.
But yeah the page is a plant probably done by the killer to distract from his true motives and beliefs.
No, I think it was created by someone after the fact, to troll the media. Otherwise, the Wayback machine would have captured it before 9:00 PM last night.