Yes, of course Vattel wrote in French. I find your point in post 176, “that de Vattel defined a phrase in English that he never used”, to be deliberately confusing. So we can only quote the French version? Or we have to say, “In French he said...”
Yes, you are correct of course; he did say it in French. But hm ... I find that kind of “truth” to be slick, oily, and well, insincere. You hurt yourself with that I think.
You can quote an English translation, but you can't claim that de Vattel said "natural-born citizen" or that "natural-born citizen" is the only way to translate "les naturels." As demonstrated in The Venus, Chief Justice Marshall himself did not use the 1797 translation which employed "natural-born citizen," and The Venus was decided in 1814.