EntitySerializer returning mystring as empty when trying to query Memory, CPU, Voltage, and several others

After this line:

mystring = EntitySerializer(deviceObj, StringFormatter('
'), templist, modfd_excl_inst, deviceType,primaryStatusOnly, tempDict).visit(componentname).formatter.mystring

mystring is empty. I'm able to run the below code and connect to the iDRAC:

import os
import sys
sys.path.append(os.getcwd())
from omsdk.sdkproto import SNMPOptions
from omsdk.sdkcreds import UserCredentials,ProtocolCredentialsFactory,Snmpv2Credentials
from omsdk.sdkinfra import sdkinfra
ipaddr=" "
commString="public"
creds = ProtocolCredentialsFactory()
creds.add(Snmpv2Credentials(commString))
sd = sdkinfra()
sd.importPath()
idrac = sd.find_driver(ipaddr, creds)
idrac = sd.get_driver(sd.driver_enum.iDRAC, ipaddr, creds)
idrac._DeviceKey

But going further and having the sdk visitor query the idrac, as in the first line quoted which sets mystring, doesn't work. As such I end up with 'No response from the host.'

Any ideas?

The iDRAC is obviously up, snmp agent is obviously enabled.

What is weird is I can query Controller, Server Information, Overall Health, Physical Disk, and Virtual Disk. However I can't query Amperage, Battery, CPU, Fan, Memory, Power Supply, Temperature, or Voltage. This is a C6420 which I have dozens of and I can query most of them just fine.