1) If you don't wipe down with acetone or IPA, it is a very good possibility.
2) A lot of soaps have surfactants, dyes, fragrances and other unknown stuff. So nothing good and likely contamination in your finished material.
3) Dispose of it properly and use new napatha. Recycling is great but 'when in doubt, throw it out' is a good rule of thumb for chemicals as well as food. If you don't know what the contamination is or how to remove it you do not want to use it. Sometimes it just cheaper and better to buy new even if you could clean it.
"Whereas modern cynicism brought despair about the ability of the human species to realize laudable ideals, postmodern cynicism doesn't —not because it's optimistic, but because it can't take ideals seriously in the first place. The prevailing attitude is Absurdism. A postmodern magazine may be irreverent, but not bitterly irreverent, for it's not purposefully irreverent; its aim is indiscriminate, because everyone is equally ridiculous. And anyway, there's no moral basis for passing judgment. Just sit back and enjoy the show. " - Robert Wright
"An intellectual is a person who has discovered something more interesting than sex." - Aldous Huxley