This may work, but, look at cost and what you get. When you buy a thing of watter wetter, if you shake it up, it does not suds up. It also is a large size, like 6 - 8 oz that you can put in, depending on your application.
If you are using soap, you put in 2 drops, I don’t see that being as effective. Water wetter is like 7 bucks, soap is like 3 dollars. Do you really want to experiment with something that is a backyard trick to save 4 dollars, or do you want to get something thats been proven over and over.
I’m all for saving money and being creative, but at a certain point, re-inventing the wheel seems silly. If you could run piss in your radiator because it has the same properties as coolant, I still wouldn’t do it.
–mark