the skinnybass plan at this point is to gather info and come up with a plan ;).
There will definitely be problems, since I don't have executive control over the site. But...one thing that I know could help is to take the most common problems and name threads after them that will knock on the highest performing key phrases. The name of the thread translates to the <title> tag on the page, which is a fairly big deal.
Next I'd try to find who has administrative access to the site, and talk to them.
But for now it is still just....come up with a plan.