Do you have a pic of the problem? Sounds like you should call GM, ask for clarification from them and/or try another dealer. The language in the OM WalleyeMike posted is pretty clear that everything is covered related to materials or workmanship during the bumper-to-bumper period.
I do have a pic but doesn't do much good. I'm taking it back for other issues in a few weeks and they're going to gather their own pics then and send to GM. But yeah, I agree regarding the language in the warranty booklet. I'm fairly certain she was just feeding me some bs in hopes that I'd say "ok" and move on with my life because when I pressed her about where I could read about this 12k adjustment warranty and what it included (I was honestly just curious to know what's covered and when if not under the normal 36k mile warranty) and instead of simply telling me where I can read the details about the warranty she just said she'd take pictures when the vehicle came in and send them off to GM. It's entirely possible there is in fact a 12k "adjustments" warranty, but I've thus far been unsuccessful in finding reference to it and if there was one, then I can't imagine they'd agree to send it to GM to try to get it fixed when I'm at about 22k miles currently. At that milage, I'm well past 12k and thus even if there was an issue, GM would just tell me to pound sand anyway.
I would start w/ the Service Manager, if that is who you talked to, ask for the Sales Manager to see if they will make it right. If not, as for the dealer General Manager.
If none of that works, tell the Dealer GM, and his staff that you intend to file a complaint w/ General Motors...that should get them to move.
Might not hurt to grab your Warranty manual and flip to the page, and tell them you don't understand how this is not a "defect in materials or workmanship."
Thanks. Sound advice and pretty much what I did with the manager I spoke which who I believe is a service manager. To her credit, she was very nice about it and I was doing my best to not sound frustrated by the whole situation. She's going to take pics next time I come in and forward them to GM to see what's next. She basically said this panel is just held on by double-sides tape and if we take it to a collision center for them to repair and they take the panel off then it's likely it will never be back on the same and may even make it worse. She said if GM were to replace the part then they've got to get the part, try to match paint, etc. and she guaranteed me the paint would never match given the vehicle is two years old and she didn't want me to have that additional nagging thing to worry about.
Where is the GM rep we used to hear from? In remember several posts a while back where his opinions were helpful. Unless you are on an island, I would check with another dealer or contact the BBB and someone from GM will be calling you.
Haven't seen a GM rep around, but admittedly I'm not here a ton. That would definitely be helpful if they chimed in with more insight.