CWB Search for Manger - HR Admin unable to find Ex-employee even when preference date set in past

HR Administrator sets CWB Preference for "Session Date" to a date in the past when a plan was open, manger was an active employee, and assigned as employee's manager.  Attempts to "Search for Manager", no employee name, number or email found.  Unable to "Switch to this manager".

Workaround is to search for one of his direct reports, at the time, who is still an active employee.  The Ex-employee will be returned as the listed Supervisor Name and the Switch to this Manager icon is present.

Is there any setting that will allow searches in CWB for Ex-employees?