CarMax review: After carmax replaced missing bumper sensor, carmax lied to me no evidence of wreck!

I am within my 90 Day Warranty on the 2021 Toyota Avalon Limited I purchased from Carmax (it expires 09/15/23). When I purchased the car one of the sensors was missing from the bumper which Carmax said probably just fell inside the bumper and they replaced it. Also on the day of purchase and again when I took the car to Carmax Service I pointed out that the rear Driver side panel was not lined up and asked if they would put a clip on it to eliminate the gap. I was told on purchase date that could be fixed with a clip and when it was serviced for the sensor I asked that it be clipped. Service replaced the sensor and I was told that the panel gap was just normal. Today I took the car to a dealership (per suggestion of the Carmax Service Manager and also since it is still under mfg warranty until November 2023) because my other complaint was driver door/window wind noise that Carmax Serice was unable to fix. I asked the dealer about clipping therear panel gap as well, and if not covered by the mfg warranty to let me know what it would cost me to fix it. I’m so upset to learn from the dealership that the bumper apparently had damage and there was. Drywall screw there holding it together instead a clip. And that I need a new bumper! I was not told of this at anytime by Carmax and there is no way that Carmax didn’t know this when they replaced the sensor (which was also within the 30 day return window! I’m devastated to learn that Carmax has deceived me and now my car is worth less because it’s been wrecked and that the bumper needs replaced!