2018 BMW 640I Suspension Problems

I took the car in for a service and mentioned that there is a slight vibration at highway speeds. The dealer performed wheel balancing and found that the issue was still there. Following this, a software update was performed and the issue was still prevalent. The final cause was identified to be the control arm bushings. The problem I see is that a number of bushings/rubber parts are failing in the vehicle and I am being asked to pay out of pocket for what I believe is a defective part/vehicle. In the first instance, the guibo/ flex disk had cracked which was replaced. These are parts that should not fail until about 80k miles while my vehicle only has 28k miles and is barely out of new car warranty.