Talked to MAN-go. He said degreaser, (he tried gojo (sp) something that cleans mechanics hands and that worked) I didn't feel like looking in the garage, so I googled degreasers, and found that link I sent you, and I read about it one of his laundry industry mags.
****BUT, but he
never tried the Wd-40 and said it stains his clothes, but he never tried applying the Dawn to it because he doesn't care because they're work clothes anyway, so he's not sure it will work,
so best not to take a chance. ****
The stuff we used on the towels was called Spot Shot. It actually is a carpet cleaner.

Some towels the stains came up that didn't work with Shout, and some it made them less noticeable, and others it did nothing for.
Unfortunately, not knowing what caused the stain, I can't say what it lifted.