Hmm. I suppose you are right. I would think that at least the many Virginia land owners--Washington, Jefferson, Madison, Henry being the most notable--fairly understood land as property, and probably thought it synonymous with happiness to own land. My point, which isn't so much a point as a musing prompted by your article (I haven't the scholarship to make points on this matter), is that those who were actively involved in taking land from the natives, must have understood in the process that a right to property is based on force; first the force to take the land, then the force to make and keep the rules that govern ownership.
Then, of course, one remembers that these same individuals not only treated the right to property inconsistently depending on your cultural makeup, they treated ALL liberty in such a way, as evidenced by the African slave trade. When I get around to studying John Adams, I will be interested to see what he may have said or written or done regarding the native American tribes.
My guess would be the same as yours, that the Founding Fathers were keenly aware of the cultural foundation of property, -- they had to be, given the Indian tribes and the slavery.