The fastest, surest way would be clear direction from Church leaders, but they didn't cause the problem. They have consistently and persistently taught that there is one Cumorah and it is in New York.
It is the M2C* intellectuals who have repudiated the teachings of the prophets and have thereby caused the confusion in the Church. It is up to the intellectuals (especially the M2C intellectuals at BYU, CES and the Correlation Department) to change course and align themselves with the prophets, not the other way around.
They can do this in three easy steps:
1. Accept the teachings of the prophets about the New York Cumorah.
2. Stop trying to vindicate the anonymous articles in the 1842 Times and Seasons, which are the foundation for the Mesoamerican limited geography theory in the first place.
3. Instead of inventing interpretations of the Book of Mormon that are designed to fit M2C, re-read the text and see how it vindicates the teachings of the prophets and is consistent with the archaeology, anthropology, geology and geography of North America, culminating at the New York Cumorah.
These three steps would be easy but for the decades-long promotion of M2C which has imprinted Mesoamerica on the minds of the Latter-day Saints.
Not that the intellectuals have bad intentions; they were trying to reconcile what they perceived to be two inconsistent teachings: (i) the New York Cumorah and (ii) the anonymous articles in the 1842 Times and Seasons about Central America.
The intellectuals chose the latter, developed M2C and rationalized their repudiation of the prophets by claiming the prophets were merely expressing their opinions, and they were wrong.**
Then they found a series of illusory "correspondences" between Mayan and Nephite culture, and voila, we end up with Mormon's Codex: An Ancient American Book, along with the entire M2C citation cartel supporting it.
Here are some of the M2C interpretations of the text that have no basis in the actual text, but instead are merely a description of ancient Mesoamerican culture designed by the M2C intellectuals to buttress the illusory "correspondences" the continue to cite.
1. Millions of people. M2C intellectuals insist the Book of Mormon culture involved millions of people. That's because we know there were millions of people in ancient Mesoamerica, so they make these large numbers a "requirement" of the text.
But nothing in the Book of Mormon refers to millions of people except Ether 15:2. Even there, Coriantumr was looking back at an indeterminate time frame:
He saw that there had been slain by the sword already nearly two millions of his people, and he began to sorrow in his heart; yea, there had been slain two millions of mighty men, and also their wives and their children.
Nothing in the text states or implies that these "two millions" were killed at once. Coriantumr saw that two million of his people had been "slain by the sword," but the Jaredite records of war went back 30+ generations. Even if Coriantumr was thinking only of those who died in his own lifetime (and there's no reason to conclude that), if he lived 50 years, that would be an average of 40,000 killed per year.
There are two places in the Book of Ether where specific numbers are given. First, we have a battle described as "exceedingly sore." Yet only "many thousands" were killed. Moroni doesn't even the common term "tens of thousands."
Ether 14:4 - And it came to pass that the brother of Shared did give battle unto him in the wilderness of Akish; and the battle became exceedingly sore, and many thousands fell by the sword.
Presumably there were other battles that were "sore" but not "exceedingly sore." Otherwise, the term "exceedingly" would be meaningless. Granted, Moroni uses the term "exceedingly" far more than other writers, but it still means something that exceeds something else.
The second placed where specific numbers are given is during the final week-long battle at Ramah (Cumorah). There were 59 men left on the last day and 121 the day before, which means that about 50% of the men were killed between those two days. A 50% kill rate extrapolated backwards means there were fewer than 10,000 people involved from the outset.
There are lots of ways to interpret these passages, but one way is to interpret it to be consistent with what the prophets have taught, including President Cowdery in Letter VII.
The point here is that nothing in the text requires millions of people. I've discussed this in more detail here:
2. Extensive ancient writing. M2C intellectuals lately have insisted that there must be evidence of extensive ancient writing dating to Book of Mormon time periods. Again, this "requirement" was invented to justify M2C, but it's not a requirement in the text. If anything, the text contradicts this requirement because (i) the surviving Lamanites sought to destroy records, (ii) the only engraved stone mentioned in the text was so unusual that the illiterate people of Zarahamla brought it forth to be translated, and (iii) the writing in Mesoamerica is anything but Hebrew/reformed Egyptian. The M2C argument is like saying evidence of writing in ancient Shanghai means the Bible took place in Shanghai because the Bible refers to writing.
I've addressed that in more detail here:
3. Extensive stone cities. M2C intellectuals always insist the Nephites built extensive stone cities and massive temples because the text refers in one chapter to some Nephites building with cement (Helaman 3). But the text says people built with cement and wood, not with stone. The only stone structure mentioned anywhere in the text is a stone wall (Alma 48:8). The Nephites fought with stones, they decorated with stones, they punished people with stones, and they translated with stones, but they didn't build with stones.
According to the text, the last thing we should expect to find are buildings made of stone. Yet that's what M2C intellectuals insist we find.
I've addressed this in more detail here:
4. Joseph mistranslated the text. M2C intellectuals teach that Joseph mistranslated the text, by dictating terms such as horse instead of tapir, sheep for an undetermined Mayan animal, etc. Joseph must have mistranslated because he never mentioned the big three Js (jade, jaguars, and jungles) or the other indicia of Mesoamerica (volcanoes, Mayans, pyramids, etc.).
Instead, the text refers to things common among the Moundbuilders of North America--the very mounds that Joseph himself constituted evidence of the divine authenticity of the Book of Mormon.
Things such as when Captain Moroni in Alma 50 caused the people that "they should commence in digging up heaps of earth round about all the cities, throughout all the land which was possessed by the Nephites. And upon the top of these ridges of earth he caused that there should be timbers, yea, works of timbers built up to the height of a man, round about the cities. And he caused that upon those works of timbers there should be a frame of pickets built upon the timbers round about; and they were strong and high. And he caused towers to be erected that overlooked those works of pickets, and he caused places of security to be built upon those towers, that the stones and the arrows of the Lamanites could not hurt them."
Notice, nothing about stone buildings or pyramids, but merely descriptions of exactly what archaeologists find throughout the Midwestern United States, dating to Book of Mormon times.
Book of Mormon geography is challenging because there are so many possibilities that fit when we put Cumorah in New York. Right in the Midwest where Joseph identified them, there are thousands of ancient Nephite mound sites that match the description in the text; the challenge is choosing among them.
Which leaves us with this choice between the prophets and the intellectuals:
*M2C is the acronym for the Mesoamerican/two-Cumorahs theory.
** Church members who pay attention know what President Ezra Taft Benson taught about this type of rationalization:
"The learned may feel the prophet is only inspired when he agrees with them, otherwise the prophet is just giving his opinion—speaking as a man."