Even if you can correct the colors, I have a couple of questions. Are you using a static
image? If so, will this be the same
image throughout the show or will you have different static images? The reason I ask is that you may need to change your correction per
image.
Also, is the gloss factor the same across paint surfaces? If not, no amount of
color correction will be able to match your
image for all viewing angles.
I don't work with
Qlab generally, so I don't know specifically how to do this. If possible, I would create a white mask in the areas you need to color correct with an alpha
channel for the areas you do not. Then I would
fade that layer in and color it as needed.