People often ask for a simple explanation of Book of Mormon geography.
Here's a summary of the entire debate in one graphic. Those who accept the Book of Mormon as an actual history of real people also accept one of these two assumptions. Then they rationalize their choice (confirm their biases) accordingly.
It's very simple.by every prophet/apostle who has addressed the topic of Cumorah. But Oliver takes the blame/credit for putting it into print (even though historical evidence shows Joseph taught it even before he got the plates, which he means he learned about Cumorah from Moroni.)