The general rule for pulsations is if you feel it in the steering wheel the brakes on the front are the issue. If you feel it in the seat or just the pedal, then normally it is the rear brakes.
Based on this info, I would at least remove the rear wheels and check the runout of the rear rotors. Otherwise, I would do the exact something to the rear brakes that you did to the front.
Here is a guide that will help if you need it:
Also, I attached the info from the manual, but it sounds like you don't need it.
Let us know what you find with this.
Images (Click to enlarge)
Wednesday, October 13th, 2021 AT 4:47 PM