If you have a second car and can live without driving you Denali for a couple weeks, maybe check with a local tech at the dealer or if you are capable to remove yourself...I pulled my bumper off and took out the grill and the whole center section of the grill unscrews leaving just the chrome surround that you can remove, as well the fog light surrounds, the Fog light surrounds can stay together with the black plastic and you can box it up and ship it to me and I can have my body shop color match the parts to the factory paint, just get me your Vin and I will get it done for you and sent back. Probably would be a 2 week down time, but when I did mine it was about $450.00 bucks, and then I just put everything back together myself. Be sure when removing the bumper, you line the area under the headlights with masking tape, and also the sides where the fender and bumper meet at the top, and be sure to lay down a large thick blanket to work on removing the parts.
Just an idea if you want. For some reason so many body shops are afraid to paint factory Chrome, probably because there is really little money in it for a good amount of work, the chrome needs to be sanded and scuffed and then primed really good in order for the paint to stick really good, also there is a special primer used in the process for plastic parts. I have no issues with paint flaking, and the color match is 100%. The other option is to check with a few more body shops in your area to see if they will do it? Out here in Cali it is pretty saturated, but only a few paint shops are willing to do this stuff, it is limited mainly due to the fact it is not a big money maker for a good amount of paint work and prep.
Anyway, you would be amazed at how different these parts painted make the truck look. Again, just a suggestion to help you if you want.
Jim