No, no, no, no! For god's sake don't use a C-41 BLIX bath. That'll remove the entire image, and you'll just be left with blank brown film.(posted 8506 days ago)The orange mask is self-coloured coupler dye that gets partially destroyed in the colour developer of the C41 process. Try putting the film through C41 developer only, followed by a wash. It might reduce the density of the dye. If not, then a chemical bleach, such as very dilute hydrochloric acid, potassium metabisulphite, or sodium hypochlorite (household bleach) might work.
The aforementioned chemicals are used as colour reducers for overexposed or colour-biased slides, so they're reasonably safe for film, provided they're followed by a thorough wash.