When I worked at CVS, the company used SAP SuccessFactors to handle processing of performance evaluations (and probably other HR-related tasks I don't know about). As part of this suite there is an organizational chart function that shows how direct reports are related to their supervisors, right up to Larry Merlo. It will tell you who is Rx supervisor for what district # and so on and who the RXMs are under the Rx sup.
I was able to access this through myHR.