I cannot find anything in the manual that says anything about how to specify a JES DESTID value in an RPS definition.
A system printer can be defined using the RPSDEST macro. See Chapter 8. ROSCOE Printing Services (RPS) in the CA Roscoe System Reference Guide. You may also find useful information in Technical Document TEC417431 RPS - Roscoe Printing Services - What you need to know.
For a system printer, the pname is set to the JES DESTID for output to that RPS destination. The information on the JES DESTID is in the manual, but can be hard to find. You will find this sample definition in Section 8.5 of the CA Roscoe System Reference Guide:
Sample RPS Definition - 1 RPS001 RPSGEN PLOC1 RPSDEST PRTR1,PRTR2 PLOC2 RPSDEST PRTR3 SLOC1 RPSDEST pname,TYPE=JES DLIST1 RPSDLIST PLOC1,SLOC1 DLIST2 RPSDLIST PLOC2,PLOC1,SLOC1 GROUP1 RPSTERM TERM1,TERM2,DLIST=DLIST1 GROUP2 RPSTERM TERM3,DLIST=DLIST2 RPSGEND
"SLOC1" is a sample definition for a remote JES printer. The pname for this printer must be the remote JES DESTID, for example "N4".
If you have more than one node name, you can set up multiple system printer id's as shown in this sample below:
... N4 RPSDEST N4,TYPE=JES N6 RPSDEST N6,TYPE=JES ...