Hereflow integration issues with Pixracer

I am using hereflow camera with pixhawk 2 hardware. I want to move to pixracer, however, I can’t get the driver to work. I am using latest Copter 3.7 as per the documentation. I am getting BAD OPTFLOW HEALTH error while interfacing it with Pixracer. I am able to set all the parameters.

Is the Hereflow camera even compatible with Pixracer? If not what do I need to do to add the support?