All metallic paint jobs specifically silvers have what is called “Paint Flop” look it up. Basically it has to do with the amount of reducer mixed with the paint and the how the metallic particles lay on the surface. The paint can look identical from a perpendicular vantage point. But when viewed at an angle, the paint reflects back either darker or lighter. It has to do with how far away the metallic particle sits in the base coat, the allignment. The case is looking at the surface as close to perpendicular as possible. The manner in which the painter sprays the coating is also as important. Silver is the toughest color to match. Yes I do agree that a perfect match from plastic to metal surfaces almost never matches. I have seen this on brand new Porsche silver finishes. Maybe it is the lighting who knows. I would get a paint meter or something.

No expert but it’s what I have seen on silvers.