Well, according to VartanHo, Mrs. Dixon does make an appearance in this episode. Check out the Guest Star list:
Guest starring Christian Slater as Dr. Neil Caplan, Greg Grunberg as Weiss, Yvonne Farrow as Diane Dixon, Tracy Middendorf as Elsa Caplan, Arthur Young as Aaron Caplan, Yasen Peyankov as Morgan Nickovich, Sean Casey as sedan agent no. 2, Jess King as cell block guard, Justin Wade as drug store employee, Eve Kagan as sorority girl no. 1 and Stacey Scowley as sorority girl no. 2.
Now I'm wondering what's up with the sorority girls... Hmm.