The 1874 RLDS edition changed the plural sufferings to the singular suffering, perhaps under the influence of the following singular nouns, death and resurrection. The 1908 RLDS edition restored the original plural sufferings. In modern English, the singular suffering is expected, as in the phrase “Christ’s suffering and death”. Interestingly, the Book of Mormon consistently prefers the plural sufferings when it is conjoined with death; all the occurrences refer to Christ:
In two of these cases (Alma 22:14 and Moroni 9:25), as Oliver Cowdery was copying from 𝓞 into 𝓟, he initially wrote the plural sufferings as the singular suffering, but in both instances he corrected the singular to the plural. Thus there has been some tendency in the history of the text to replace the unexpected plural sufferings with the singular suffering. The critical text will, of course, retain the consistently used plural sufferings when it is conjoined with the noun death.
Summary: Retain in Alma 16:19 the plural sufferings (and elsewhere in the text when sufferings is conjoined with the noun death).