Brake Disc Pads problems of the 2008 Ford Mustang

Car was taken to Ford dealership for airbag recall and all 4 wheel brake job (12-2017). 7 months after a grinding and pulsation presented itself in the brake pedal under medium to hard braking conditions while driving the car. It felt like the abs was kicking in and caused driver to drastically adjust braking and steering because you thought your brakes were failing and your car was out of control. The car was returned (7-2018). Dealer replaced front pads and machined rotors, but the grinding and pulsation returned. Back to the dealership (8-2018). They machined rotors again, but problem returned. Back to dealership (10-2018). Replaced all pads and rotors. Ok for short time but the grinding returned. Car was parked due to safety concerns. Took to another dealership for a second opinion (9-2019), they verified the complaint. But was told they couldn't find anything. Tires balanced, brake fluid changed, suspension parts tightened but the grinding persisted. The car felt unsafe. Basically, was recommended everything should be scrapped and start over with all new brake parts. I couldn't afford dealership price a second time in 20 months, so did it myself with name brand, nationally recognized parts. All pulsation, grinding, thunking, vibrations and excessive sensitivity to road conditions disappeared. Upon closer inspection, found the oem motorcraft anti-rattle shim had detached from the brake pads and began migrating around the back of the pad. Less than 10k miles and 7 total trips to the Ford dealership and I had to throw all the Ford parts out and fix the problem myself. Original dealership refuses to refund my $1k for the original work. Ford knew pads were defective and still sent customers out the door with faulty brakes. Large safety concern, or an overall scam to defraud consumers for repeated brake repairs-not sure, but it's unacceptable.