My advice would be NOT to apply any cutting wax - its easy to make a hash of it. If it's that bad and you want it sorted promptly, have a specialist detailer deal with it.
I had a Bentley recently that was 'diamond black' a really very deep black. I had an avian cow pat on it that seemed to have damaged the paint. However over a few washes and a 'normal' Autoglym type wax (which is mildly cutting in any event) the mark gradually disappeared.
Try a few gentle washes and a few normal waxes.... You might get lucky.
