That the founders insisted on using the word “Citizen” means we got it’s meaning from Vattel....”
No, because the direct American experience with the usage of citizenship to denote urban and/or national citizenship long predates the birth of Emer de Vattel. Vattel’s works only restated what the North American colonists had been personally acquainted with since the founding of the Jamestown and Plymouth Colonies through their contacts with other Europeans in Europe and in the Americas. In particular, one of the huge influences upon the Founders was the Dutch Republic and its former colony in North America, the 17th Century Colony of New Amsterdam. See for example:
New Amsterdam - Notable Citizens
https://www.geni.com/projects/New-Amsterdam-Notable-Citizens/5376
Your link makes no reference to the use of the word "Citizen" in New Amsterdam. The word I see being used back in the 1600s was "burgher".
Do you have any links to documents showing the Dutch were using the word "Citizen" rather than "Burgher?"
I would be very surprised to find the Dutch using the word "Citizen."