A summary of 2 Nephi 29 is that the new revelation divinely granted to Joseph Smith confirms Christ intended to confirm the Nephites under the wing of the Jewish blessing and lineage. And John 10:16 and Matthew 15:24 are used in justifying that belief.

But from simply this passage; one could argue that the teachings of Mohammad could lead you to God because you’re hearing a prophet’s voice or maybe the Nephites are the “others” from what Joseph Smith taught about Jesus going to the Americas after his resurrection. Or maybe the “others” are anyone who sits in a quiet room emptying their mind in a calming pose and waiting to hear what comes.

However, if the common held LDS opinion about the Nephites are true ; then salvation through Christ is only granted to the Jewish lineage because the Nephites are supposed to be a lost tribe of Israel.  (Even though there’s no DNA evidence linking American Indians to Jews).  If so, we can all pack up here and go home, you’re out of the salvation club if you weren’t born into the right family.

But Paul in writing to the Ephesians elaborates on the greater purpose of Christ.

Yes, Jesus was sent unto the lost sheep of Israel (Matthew 15:25). But as a Jewish prophet and a Jewish priest and the Jewish Messiah, turns out his greater purpose was in his eventual rejection by the Jews so that the “other sheep” … the gentiles … could accept his salvation.