Rman duplicate with target no catalog - backup location question

On my auxiliary host, the copy of backup is on a different directory than the target '/opt/stage/backup/primdb'

On target host, backup directory is '/opt/oracle/backup/primdb'

Running duplicate from auxiliary:

rman

rman> connect target sys@primdb

rman> connect auxiliary sys@auxdb

rman> duplicate target database to auxdb backup location '/opt/rman_backup/primdb';

Duplicate fails as the backup is being looked for in '/opt/oracle/backup/primdb'

As a workaround, creating a soft link to /opt/stage/backup/primdb as /opt/oracle/backup/primdb in the auxiliary host would allow the duplicate to run.