Hi
If you got it working for RQM(QM), but not for DOORS, then it seems that your requests are valid. The problem is likely to be in the configuration of DOORS. Maybe you don’t have the authorisation to access this data in Doors?
Are RQM and DOORS of the same version/release?
Can you share where you got the code you share above from? this way we can see how updated it is.
Here a tip on under Lyo-samples a more recent piece of code where a client tries to communicate with an OSLC server. It might get you started on how to work with oAuth.
Try to see if that can be used to access both your servers