sorry about the luck, find a good shop with a painter who takes a little pride in their work, unfortunately that light pewter(382e) code has atleast 6 varients or alternates; gm uses a lot of the corvette color codes on other models and a truck painted with the same code probably has a very different color on it...so when your paint gets mixed you usually end up with a bad match, i know this because I paint at a collision shop.
I have atleast 5 sprayed out versions of the pewter and can usually find a great blendable match, keep in mind you need room to blend the color over the damaged area and clear the whole panel, this color must not reach the edge of the panel or it will likely look like the wrong color, this is why you often end up blending into the next panel, even with the closest color matches you need room to blend.