I bet the paint supplier where your hood was taken used a spectrometer to create a perfect color match formula. This tool measures the refraction of light. Your original paint could be ever-so-slightly off (from the actual color code) to create the mismatch. The spectrometer will help in calculating the specific ratios of different pigment needed to custom mix a quantity of paint that your painter can use to "reshoot" your hood.
I worked at a dealership that did not have a body shop. We used an independent body shop across the street that used a spectrometer. We would have customer's come in who shearded off a colored outside mirror or damaged a bumper fascia etc. We would drive the vehicle accross the street. The body shop would take the color code of the vehicle and then clean an area of the adjacent panel and shoot it with the spectrometer. The car would go back to the customer for a few days while they painted the new part(s). When returned for the installation, the color was not close, but perfect. This takes into account variances created through the actual paint process, UV fade, customer care (or neglect) of the paint surface over time, etc.
My then brand new 2004 Chevrolet Trailblazer got damaged when someone made a left hand turn in front of me while I was travelling at 35-40 MPH resulting in $12,000 of body repairs. My vehicle was repaired by them and everyday therafter when coming to work, I parked my vehicle in the front of our service department entrance. When people asked of a quality shop and asked about their work, I would make my recommendations by walking them out to the truck, unlock the door and ask them to show me where the body work was done. A door skin was replaced, a quarter was welded in and they replicated every type of weld and caulk joint perfectly. I compared every part of their work from the right side (undamaged) of the truck to the left side (damaged/repaired) of the truck and could not find an error. The paint work was flawless...not a speck or imperfection anywhere. Keep in mind that this was a common garden variety Chevrolet SUV, yet their level of repair did not diminish based on the type of vehicle repaired. (I witnessed everything from Benzes to Mazda there). I no longer work for this dealership, but over a ten year tenure, I developed a relationship with this body shop. Should my 'stang need any type of body work, there is no question whatsoever where it will go.
It sounds like your painter is interested in your satisfaction and his reputation and appears to be taking the right move to "make it right".
I posted this story to say there are repairers who have the desire and determination to do it right and I commend them to the fullest. I feel someone recommending my services is the highest compliment that can be paid.
Good Luck and let us know of the results.