I feel your pain. I am a Honda owner and have been to the I-10 place to get the front bumper re-sprayed because it had picked up many scruffs from careless parking. My car is black. They were not able to get the paint right. It was dull. the body shop manager is totally non technical so is the shop supervisor. They are totally dependant on the painter. If he says the paint job is good, all or them, like parrots, repeat, "The paint is good". The front bumper spray (no dents) cost 12,000. I took the car to another shop who did a great job on my Jaguar but for some reason did not do such a brilliant job on the Civic. That cost 10,000. I then took the car to another guy in G-7. His paint was the best of all but tends to go dull every 3 month or so. I get him to re-polish the bumper with his own concoction of Brasso and compound and polish. That looks great for a few months and then its back to him for a rubbing.
So from my experience, I have yet to come across a shop/place that can do a job at par with the original factory paint job. I really don't know what to say to you except just apply paint with a brush to cover the exposed metal to prevent rust and leave it as it is. Repairing this section will always be detectable. Plus to match the colour the whole door will have to be painted. That will lead others to believe the entire door was smashed.