I just had the same thing happen with a silver Kia that had been keyed.
Painted the new upper right bumper (old one damaged), existing scratched left upper bumper, the scratched hatch,
the scratched door and the qtr panel between them.
Everything matched except the door, it's darker.
All the other panels matched great.
The pictures don't show it, but out in the sun, the door is darker.
All painted the same time.
The door had the largest deepest scratch and had more base over the sanded scratch
which didn't go through the factory primer so I didn't prime it.
I think now, that was a mistake.