As is frequent in the original text of the Book of Mormon, the biblical inflectional ending -eth has been extended to the third person plural. Most of these extensions have been edited out of the text. For further discussion, see the example of rebelleth in the 1 Nephi preface, plus the general discussion under infl al endings in volume 3.
Summary: Maintain the extended use of -eth in the third person plural; such usage is characteristic of the original text.