Can you run an snmpwalk on that OID to determine all values that could be associated to it? I’ve noticed that while a hardware vendor says use this, the result you may be looking for is actually further in the MIB tree due to auto generation of things.
To get a better idea check out my post - Leveraging SNMP to detect your mobile device
The Cisco OID while valid, generated a different string to query for the result I wanted/needed.