Yes I know, running multiple websites on 1 IP isn't smart. 6 Websites with duplicate content on 1 IP is even worse. It's a technical issue we can't solve quickly.
Thing is, our #1 website, which has the highest DA and PR, was the first website with all this content. All other websites we're running were launched a few months, and some a few years, later. All content was copied from the #1 website.
I'd say the other websites would get knocked down by Google, because they duplicated the content. Google should see that our #1 website was the first that uploaded this content. Therefore our #1 website should rank normally.
Questions is: What does Google think of duplicate content when all websites are on 1 IP? Is, or will our #1 website get punished as well?