These commands on your management should add a new user named "backupAdmin" with the password set to '1qaz!QAZ':
firewall="<IP_of_Gateway>"
scriptFile=$(mktemp)
cat << 'EOF' > "${scriptFile}"
add user backupAdmin uid 0 homedir /home/backupAdmin
add rba user backupAdmin roles adminRole
set user backupAdmin gid 100 shell /bin/bash
set user backupAdmin password-hash $6$rounds=10000$hv3SByNB$0g9QWW2Peb0KNHBQvFdMsYPmFAV9Q1HP2jsBeO5RzlqAqMZWxRNNOgTbqVqoeFclLMDYLp/ojcDqlD2JDkQrA1
EOF
$CPDIR/bin/cprid_util -server "${firewall}" putfile -local_file "${scriptFile}" -remote_file "${scriptFile}" -perms 444
$CPDIR/bin/cprid_util -server "${firewall}" rexec -rcmd clish -s -f "${scriptFile}"
Replace <IP_of_Gateway> with the address your management uses to refer to the specific box, same as before.