DCS Login from Oracle Fusion

Summary:

We have requirement to launch the DCS application from Oracle Fusion users(Internal users) and as well as for External user(Direct login to DCS application who don't have user account in Fusion). I am able to login to DCS from Fusion-Springboard if my Fusion user name is an email address, but the same is not working when the Fusion username is a non-email i.e, employee number of the user. Login is working for external users.

We have implemented SSO, so when you login into fusion and open the DCS app, it will not ask you to login again(Working for fusion username which is an email address)