has anyone configured performance advisor to show machine names?

No.  Even though you can enable it in the diagnostic tool (prior to upload), PTC has disabled the ability to access any user or machine identifiable information out of concerns about privacy.

You can't config it.  But assuming you have a startup batch file you can add lines there to get that info.  I just listed where the information for the User_ID and UUID (Computer ID) in another posting. 

How to identify a user in Performance Advisor

The batch file then can record the User_ID and UUID along with the variables %username% and %computername%.