You sound like you're talking for the devs, and again, if this is in fact how they did things, it would be very very poor coding. Far as I remember from when I actually dabbled in 3D object rendering, and I may be outdated, but texture maps are greyscale images, usually low rez (256 colors most often) that simply shows the pattern. There may be one, two or more color maps, which are often just monocolor (black and white) maps of what regions of the texture map they affect. These are tiny generic files. When an item is rendered, each pixel is tested against the color map(s) for on/off value, given a saturation based on the texture map, and a color based on the hex code for the base color.
If I understand what you're saying, you seem to think they have individual full-color (large file size) texture maps for each item and each color variation of that item in the game? If so, how are they accomplishing the match-to-chest currently? Have they pre-textured all possible color combos of all skirts, pants, gloves, wrists, belts (and presumably helmets eventually) for when we color match? Wouldn't make any sense.
Far easier to be checking the chest for their color codes and passing those as parameters to the greyscale saturation maps for the other items. In which case, as I was suggesting, swapping the primary and secondary color codes, or allowing us to chose our own, would be very simple coding and not require the attention of graphic artists or new textures at all.