Help me rescue a dress with dye run

[GhostCurry]

Hi! I have a lined dress made of fine corduroy that’s accidentally gone through a regular wash.
Dress is black with white, lilac and aqua spots. Those spots are now various shades of grey.
I’ve put the dress into cold water but I have no colour run remover. Is that what I should look for? I have basic things like Vanish oxy clean stuff, vinegar and bicarbonate. Any of that be useful?
Thank you!

Don't use vanish, oxyclean etc.
Was the dress dry clean only?

Cheers for replying :)

I used Vanish before I saw your message! It has sort of worked. Ah well. Thanks!