I could not find any references to anyone trying to query temperature using WMI
I used the following in wmi.conf
[WMI:Temp]
interval = 60
namespace = \\.\root\wmi
wql = SELECT CurrentTemperature FROM MSAcpi_ThermalZoneTemperature
index = default
disabled = 0
This will give you the temperature in kelvin, then need to convert to Celsius by subtracting 2732 and dividing the result by 10
It looks like the WMI polling CPU is limited, in my case it always returned 29 degrees celsius and did not change.
WMI does not look to be a reliable CPU temperature monitor, your results may vary though.