Static PosHold Loiter Follow Me

I want to track a moving object as if it’s a POI. More to the point, I want to hover in PosHold over the center of a race track and follow a car around just using yaw. I’m looking to do this with some sort of Follow Me scenario and not any sort of image recognition. I can place a GPS receiver in the vehicle and use a telemetry radio back to a laptop running MP. However the road block is the default Follow Me behavior; it follows me! How can I get the craft to maintain a “static” position above the race track and have it follow this POI (a car) is it goes around the track?

One idea I have is using a 2nd Pix running Antenna Tracker to control a gimbal. I’m not sure how this would work because the Antenna Tracker would essential be upside down. Ideas?

I see some promise with the FOLL_YAW_BEHAVE param, however I am not finding something to keep the vehicle in PosHold.