The Mormon Church will be happy to do whatever Bishop Romney tells them. Especially since there was an early prophecy about a Mormon leader becoming Potus.
This certainly won’t be a problem.
The White Horse Prophecy was repudiated by the LDS Church in 1918.
In December 2009, the LDS Church issued a statement in December 2009 that:
"The so-called 'White Horse Prophecy' is based on accounts that have not been substantiated by historical research and is not embraced as Church doctrine."
The history of the White Horse Prophecy is much more complicated. I'm happy to discuss that if you wish, but only in a historical context. I'm not interested in addressing LDS theology.