I think you can't monitor device which have no snmp. On ping basis you can just monitor device reachability but no other thing like CPU, or traffic usage. Unfortunatelly CiscoWorks use snmp and CDP for device discovery and monitoring.
If you can enable snmp on device so you can manually add device to DCR and it would be able to monitor via LMS.
to test just if the device is just reachable would be enough.
But everytime I add that device it is red in Topology Services all the time.