I don't think a 100% match will be possible all of the time (if at all). They might have made a true match when printing, but you have to bear in mind that all batches of paint will differ ever so slightly; none are perfectly the same.
I used to work at an ink factory, and you wouldn't believe the lengths they had to go to, to make sure their products were within a certain margin from set color coordinates!
Also; I have had numerous Vallejo paints with exactly the same number and name being distinctly different from each other. Different batches, different ingredients and recipies; margins in hobby paints seem a lot looser than those in the printing ink industry.
So in my experience, matching paint to print will always be trial and error...