Removing vanish stain from sofa

[climber_chick]

I spilt nail varnish on the sofa today and used vanish upholstery spray. It has virtually got rid of the nail varnish but where the vanish spray spread, I now have a large dark patch left. The fabric of the sofa is a woven thick type and I can't remove the cover or turn the cushion over. Any advice on how to get rid of or make this stain less visible would be greatly appreciated! Thanks, CC:)