Textual: With this verse Mormon gets the three brethren together, and brings them to Middoni, where we know that Ammon and Lamoni will come to free them. Part of Mormon’s purpose in his history so far had been to get us to the point where the stories intersect and we have Ammon and Lamoni in Middoni. The way the history is constructed, however, gives us another clue to the source that Mormon is using for this account.
We have Muloki and Ammah as two preachers. While they might have been of a lesser status, and therefore “assigned” to a village rather than a city, nevertheless it is not unreasonable to suppose that they also might have kept s missionary journal similar to what we obviously have for Ammon and Aaron. In spite of this, we get no earlier history of Muloki and Ammah. There is nothing of their preaching to this point except these verses.
This contrasts with the account of Aaron in Jerusalem, which, though brief, is still more fleshed out that what we have for Muloki and Ammah. This suggests that Mormon is taking this full account from Aaron’s record, in which Muloki and Ammah appear. Perhaps Mormon had the records for Muloki and Ammah, and perhaps he did not. This section, however, must have come from Aaron’s record.