Speaking as a resident of a neighboring state (which had its own land issues), while this was perhaps entertainingly phrased, nothing in there sounds at all unlikely or outlandish. Assuming (which I think is safe) that his "vast hegira" happened peicemealpiecemeal rather than all at once, I find nothing whatsoever in there difficult to believe.
What is left is an entertaining exposition on the prevalence of endemic surveying errors (and the ability of the rich/well-connected to get such errors resolved in their favor). This most certainly was the case in eighteetheighteenth and ninteenthnineteenth century America, not only on the local level, but even as regards to state boundriesboundaries.
The book How the States Got their Shapes goes into this in detail. If you ever wondered about the odd little straight-edge bends some state boundriesboundaries have (see Alabama), more often than not a surveying error was involved somewhere. Just thumbing through the first third of the book, I found surveying errors having a hand in the modern borders between five pairs of states, and out and out corruption probably involved in two. The border between Iowa and Missouri was particularly interesting, in that it involved both.