Sorry Gefen: I have never found anything that will remove paint from a fabric, especially now that it is set. Occasionally, if you can get to the stain while it is fresh (still wet) some of it may be removed. Anything that removes paint, such as turpentine, will usually destroy the fabric. Have you done an internet search? Google “removing paint from fabric” and see what comes up.
Sometimes if the paint was half dry and didn’t really set in you can flick it off with a razor blade (be careful not to cut the fabric). If not nail polish remover will work but too much will destroy the fabric.
St. Moritz is great for removing stains, but I did manage to ruin a jumper of my daughter’s that way. You should test the inside first to make sure it doesn’t damage the sweater.