A good independent shop is getting harder to find. To diagnose some issues, they often need the manufacturer-specific software. Since the license fees for some of these software suites can cost over $1,000 per year, most independent shops cannot afford to maintain all of them. There can also be delays in getting parts, since they likely don't keep parts for an uncommon car like the Genesis in stock and their orders will probably be treated with a lower priority than orders from a Hyundai dealership. I've seen independent shops that specialize in the German makes, but I haven't found a Hyundai one. I recommend avoiding brake, tire, and oil change shops for anything other than brakes, tires, and oil changes unless someone you trust recommends their work. I've had brake and tire shops screw up jobs on cars that are more common and probably much easier to work on than the Genesis.
In addition to checking the regional board as previously recommended, you could also check the coupe boards. The coupes have a larger modding community, so they may be able to recommend custom shops that specialize in Hyundai/Genesis.