Bill Tindall, E.Tn.
It is common for people to simply add some solvent to remove a stain and not consider that the material has to be extracted, diluted etc, but then the solvent with stain needs to be removed by some means.

To get ball point pen ink from a shirt pocket we would back up the stain with paper towel, then add solvent from outside the stain area to wick it to the center of the stain and then onto the towel. Without a place to go the stain, or in this case oil, will just get moved around and diluted.