if they actually read the proof (they already have), they have to refute it before claiming it's false. They can't do that, so they merely restate their proposition as if repitition makes it truer.
Not much we can do about their refusal to be logical.
The big question is that since libertarianism is perfectly possible without any theory of natural rights, why are they bothering to hold outmoded false ideas?
I've proven that natural rights do not exist.
If they do not exist, I do not have the right to own people, which, btw is a right held by some humans over others throughout history, and is still exercised this day in some corners of the world.
Since I don't own people, the limits of my proper control over them are those areas in which their exercise of their own freedoms overlaps my freedoms and my life. They can't be parking their oxen on my wheat, I can't be keeping my donkey in their hut. The boundaries for such freedoms were originally based on who won the fight, and evolved as society evolved, so now our lawyers fight instead.
Too bad the lawyers don't get bloodied, but can't have everything.