What was the part about discrediting? I went back and looked but don't see it.
http://www.tvguide.com/special/finale-preview/PhotoGallery/Watch-Finales-Scoop-1045641#1045648
TV Guide Must Watch Finale's
Guest stars abound! The episode features the debut of Peri Gilpin as D.B. Russell's wife as well as the return of Jaclyn Smith as Hodges' mother. But it's Connor O'Farrell who will make the most waves when former Undersheriff McKeen returns for the first time since he killed Warrick. He'll wage war on the CSI team, which is stuck with a sensitive case that causes Russell and Finlay to butt heads. "We have a murder that is reminiscent of the case that got Finlay fired in Seattle," executive producer Don McGill says. "It dredges up deep feelings from the past between Finlay and Russell. Finlay is someone who has a tendency to, in her quest for justice, cross the line." Although McKeen will attempt to discredit Russell, he also has his eyes on Nick, who will "really, really contemplate whether or not he wants to be a CSI anymore," McGill says.