Good Morning All,
I am wondering if in the color print world, there is something akin to potassium ferracyanide in the b&w world to reduce or eradicate areas of a finished print. I've dabbed a bit of this and that on a test print, but so far no luck. All I seem to do is stain the paper with the color of the chemical.
Since the image is a color dye regular silver bleaching chemicals won't touch it. Try hydrogen peroxide or any other type bleach you would use on hair color as a starting point. No guarantees of the results though because you may get uneven reduction of the color layers that will cause wierd color shifts.