The “Lawson RQC Requisition user not able to see Service Tab” issue can crop up from time to time for select users, but it is a simple fix (see below).
After verifying the user has adequate access for requisitions and the RQ04 record is created.
Have the user clear browser cache go to Requisition Center >> Shopping >> and Press NEW.
Have the user logout and back in, check to see if the Service Tab is now there.
Also, in RQ04, you can set a value for Special/Service Items in one of the tab options to see if that resolves the issue as well.