Dragon, the dealer and GM need to address the issues of her Camaro. All of them, in fact. Just because she owns 3 GM cars and 2 of them are running well, doesn't mean GM should turn a blind eye to the third car. By GM backing up and honoring their workmanship on her Camaro would be the greatest testament that GM truly has turned the page on not only shoddy automobiles, but also shoddy customer service as well. If I was GM, I would embrace this situation, make it right and then use it as a positive example to smeer in the faces of all of GM's competitors. I'm very curious and interested to see how the dealership responds to this.
To the OP, you don't have to bring your car to YOUR dealership if they aren't cooperating with you. You can bring your car to any GM dealership for service. Sadly, even the GM crackdown on lame/shady dealerships that took place earlier this year wasn't a strong enough message to some of the still fortunate/existing dealerships. Don't feel obligated to keep returning to your original dealership.