These verses confirm the nature of the tribute arrangement. The Lamanites leave "guards" to ensure the collection of the tribute. Mesoamerican archaeology has noted the presence of "foreigners" in certain locations. The "foreigners" were from the known dominant city state of the era, and the best explanation is very similar to the Book of Mormon's. They were garrisons to ensure the tribute.
Other than the tribute, Limhi is allowed to govern his people. The Lamanites have no interest in establishing their own rule. Their interest is in the receipt of tribute. Once again, this incident is quite at home in Mesoamerica, but much less so in European or American wars.
Textual: There is no break in chapters at this point in the 1830 edition of the Book of Mormon.