Since Chemish witnesses Amaron’s entry, it suggests that Amaron made it on his deathbed. Perhaps he was fatally wounded during the war, lingering only long enough to complete his entry and transmit the record.
Redaction: Perhaps Chemish wrote his brief account in two sittings, the first very soon after receiving the plates. The phrase “and after this manner we keep the records” apparently belongs with the charge to keep the plates but with no mention of “genealogy.”
After this introductory paragraph, however, Chemish apparently had nothing to say. When he was ready to pass the plates on, he simply ended his entry. There is no indication of how long he kept them, but presumably not long, since he was of the same generation as Amaron who had them for thirty-eight years. Obviously Chemish was Amaron’s younger brother, since possession of the plates was the right of the firstborn.