Look Into Their Eyes and You See What They Know - S5-E19
Other mistake: In an earlier episode where Edie and Susan are driving Martha Huber's ashes to the lake to be spread, Edie gets a flat tire and Susan changes it. In this episode, all the girls are driving with Edie's ashes and they get a flat tire. Susan asks "Does anyone know how to change a flat tire?" Did she forget how?
Answer: He was investigating the lead not the case.