Sensor SELs showing as Undetermined system hardware failure in OpenBMC 2.7.0

[marthauk]

Using OpenBMC 2.7.0, phosphor-host-ipmid 455ee0b
Trying to display sel-entries using ipmitool sel list.
Have defined phosphor-dbus-monitor policy to flag events on sensor threshold violations

with assocations.json containing for example:

                ` "path": "system/chassis/motherboard",
    "endpoints":
    [
        {
            "types":
            {
                "rType": "inventory",
                "fType": "all_sensors"
            },
            "paths":
            [
                "/xyz/openbmc_project/sensors/voltage/<sensor>",
                ...
                ]
            }`
            
We have defined a corresponding 
`120:
entityID: 7 # system main board
entityInstance: 9
interfaces:
    xyz.openbmc_project.Sensor.Value:
        Value:
            Offsets:
                255:
                    type: int64_t
multiplierM: 2
mutability: Mutability::Write|Mutability::Read
bExp: 0
offsetB: 0
path: /xyz/openbmc_project/sensors/voltage/<sensor>
rExp: -2
readingType: readingData
scale: -3
sensorNamePattern: nameLeaf
sensorReadingType: 1 # threshold sensor
sensorType: 2 # voltage sensor
serviceInterface: org.freedesktop.DBus.Properties
unit: xyz.openbmc_project.Sensor.Value.Unit.Volts`

in ipmi-sensors.yaml

I see that the reverse association is created for the system/chassis/motherboard inventory item. I can't see any association for the sensor under the hwmon.

I'm aware of these to similar/related issues:
openbmc/openbmc#3283
https://lore.kernel.org/openbmc/CAGm54UFX9LPHArj-2q=w2pNtwgpkjZJE_0Dgd3_8cXB9z3L2vQ@mail.gmail.com/T/

As the latter thread suggests, I tried adding a threshold sensor to ipmi-inventory-sensors.yaml

/xyz/openbmc_project/sensors/voltage/<sensor>: eventReadingType: 1 offset: 255 sensorID: 120 sensorType: 2

But still ipmitool sel list shows "Undetermined system hardware failure" for these events.