The death sentence on Alma likely extended to any of his followers. Since Alma was actively preaching against Noah’s social, religious, and economic rule, he would be even more hated and hunted than when he first fled from the court.
The “borders of the land” had to include Mormon, since the record specifies that they were in Mormon. However, Mormon, although on the fringes of the land, is not out of touch with Lehi-Nephi. Alma’s people have not completely lost connection with the city.
Redaction: This verse is a transition from the story of Alma’s people to the next story, Noah’s death. Their remote location provides context for the armies of Noah who are searching for them.