Ok, here is what you want. Get Citrazinic acid, H-Acid or J-Acid. These are water soluble couplers that form greenish yellow dyes. Presoak your exposed B&W film in a solution of Epsom salts + Alkali + one of the above acids. This will cause them to stick to the film (mordant) in the gelatin. Then rinse briefly. Then run through the C41 process (no bleach or blix, just a fix) at room temp. If things go as expected you will get a black and green image.

This should work. It works in parts and pieces, as I have done it before, but don't ask for specifics. If you want this, you must do the experiments yourself. Sorry.

PE