One thing I will add… I think this is a problem with the Kickr, not the power meter or power match. I use the Kickr with a Favero power meter. My wife uses the Kickr without a power meter (she just uses the power reading from the Kickr), and has the same problem. That should eliminate the power meter and power match as variables. I’ll be interested to hear how your experiment goes.
Other things I tried that didn’t have discernible impact: updating the Kickr firmware and performing a factory spindown on the Kickr.
We both run trainerroad on our phones (iOS) and connect via bluetooth. That is one variable I haven’t tested.