So a final update in case anybody cares - the dealer did confirm that the front radar sensor issue was caused by Carmax drilling the bumper in the wrong spot (and not using a proper license plate mounting bracket). So now with the license plate in the correct location - mounted lower - I now have two holes smack dab in the middle of the bumper. 
I assume CarMax will repair or replace the bumper - not sure which I prefer. I guess whatever makes it less noticeable in terms of the paint blending and such. Any body shop gurus out there with thoughts on which course of action I should demand Carmax take (new bumper or just patch and repaint)?
I assume CarMax will repair or replace the bumper - not sure which I prefer. I guess whatever makes it less noticeable in terms of the paint blending and such. Any body shop gurus out there with thoughts on which course of action I should demand Carmax take (new bumper or just patch and repaint)?