My 2023 had rocker damage too (passenger side, same bolt location) although nothing compared to yours. Mine had a small crack right at the bolt. The dealership replaced the rocker panel entirely but it took several months (4.5) to get a replacement panel from GM and I kept driving it in the meantime. I was the second of about six 2023 cars my dealer received with similar cracks and ALL had their panels replaced. My dealer thought it could be a 4 day job, so gave me a loaner. The replacement panel arrives unpainted, so it's color matched. Like
turbozig said, it's glued on as well so it's fun to remove and a bit more complex to put back on. But my dealer didn't take as long as expected and I got the car back on the third day. Perhaps "practice makes perfect" or in my case, a quicker job. The car looks/runs 100% AOK; it's like it never happened. Just the hassle of losing it for a few days. Keep in mind with the new paint, you need to allow it to cure for a few months, so don't throw a car cover over it. My dealer later on in 2023, said they stopped seeing that on their new C8's so they thought it had been solved. They said it was definitely a transport problem. Apparently, this s**t is still happening. Sorry to hear but hopefully you can keep driving your C8 until it's fixed (assuming you're taking the car like that) and you'll soon be "right as rain". Good luck!