How so? I see no difference whatsoever.
He explained his reason. Are you 150 years old, or do you mean “see” in some other sense of “it’s how I feel so it must be true”?
Otherwise, you could present your first-hand accounts of mormon marriage in the 1800s, and explain how he got it wrong.
Judging only by the description he gave, and what we know about FLDS, they are remarkably different.