SSO integration between OIM and PeopleSoft where OIM AD user ID is different than PeopleSoft OPRID

We are in planning phase for implementing SSO between Oracle PeopleSoft FSCM9.2 and Oracle OIM.

We have OIM which is using our Central Active directory User IDs which is different than User IDs(OPRID) we are using to login to PeopleSoft. We tried using OPRID alias but It did not work.

If we try to create a new user with OPRID similar to Active directory user, It works but this solution is not feasible considering the number of users and business requirements.

Has anybody implemented any solution where IDs are different in PeopleSoft and third party SSO partners? Any lead would be appreciated.