OpenXR with Vive Pro Eye in Unity 6

Unity Engine
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1

I wanted to see if I can get my (old) Vive Pro Eye eye tracking working with just the OpenXR loaded. So not using the ViveSR plugin. Just a dummy scene with XR Rig. Added a sphere that should follow my gaze. So this runs in my Update():

    private static readonly List<InputDevice> InputDeviceList = new List<InputDevice>();
    private InputDevice eyeTrackingDevice = default(InputDevice);

 if (!eyeTrackingDevice.isValid) 
{
     InputDevices.GetDevicesWithCharacteristics(InputDeviceCharacteristics.EyeTracking, InputDeviceList);
     if (InputDeviceList.Count > 0)  
    { 
     eyeTrackingDevice = InputDeviceList[0];   
    }
     else { Debug.Log("No eye trackers found!"); 
         return;}
    }
 }
 else
 {
 wasEyeTrackingValidLastFrame = true;
 bool hasData = eyeTrackingDevice.TryGetFeatureValue(CommonUsages.isTracked, out bool isTracked);
 hasData &= eyeTrackingDevice.TryGetFeatureValue(EyeTrackingUsages.gazePosition, out Vector3 position);
 hasData &= eyeTrackingDevice.TryGetFeatureValue(EyeTrackingUsages.gazeRotation, out Quaternion rotation);
 if (isTracked && hasData)
{
     transform.localPosition = position + (rotation * Vector3.forward);
     transform.localRotation = rotation;
 }

It finds the tracker and it returns data that looks sort of okay, but is off. So, I see the little sphere match my eye movements, but it’s offset and the range (angles) is too small.
Now as I understand position is the mid-eye position as seen by the tracker and rotation is the combined look direction of your eyes. Combining these two should get a vector starting at mid-eye and pointing towards the gaze direction.

I’ve also tried adding a Physics.Raycast but looking at those results I see it is also off.

Anyone know why it does work but the results are … off?