I would try searching for something that will remove it. Anything too caustic will kill your shorts too, so you'll have to do searching on what kind of "lite" chemicals you could use.
NEver heard of crud cutter. I got some paint stains from painting the house so can you ask your mom where she got that? Also for Oil stains use gasoline. Just thought id throw that out while we are on the subject of stains. Gas also pwns bees.