Here the printer’s manuscript has the singular pronoun he, not they. The 1830 typesetter changed the he to the plural they. The original manuscript is not extant for the he, but he fits better than they given the space between surviving fragments. On the other hand, the preceding plural pronouns themselves and them are extant in the original manuscript. But it is possible that the them is actually a mistake for him, especially since both are pronounced identically (as ’em /ßm/) in casual speech. Errors mixing up him and them have been found elsewhere in the original manuscript (see, for instance, the discussion under 1 Nephi 10:18–19). In other words, Joseph Smith may have actually dictated “there are some among you which would humble themselves / let him be in whatsoever circumstances he might”. The tendency to misinterpret the him as them would have been prompted by the preceding themselves. On the other hand, the chances of an original they being replaced by he, especially given a preceding them, seems quite implausible. If there is an error here in Alma 32:25, most likely the them is an error for him.
There is considerable switching between singular and plural pronouns in the text, especially in generic statements (see the many examples listed under 1 Nephi 17:48). In virtually all cases, the switch in number is found in different clauses, as in the following example:
This kind of usage would support emending the them in Alma 32:25 to him:
There is one case, however, where in the original text the switch in number is within the same clause:
But in this example, the third person singular mine Only Begotten Son intervenes between the he and the their. The use of the original their prevents the reader from misinterpreting the other possibility, his, as referring to the nearest third person singular—namely, mine Only Begotten Son—rather than the earlier generic he.
Ultimately, the switch in number in the earliest text for Alma 32:25 is just too jarring to accept. Given that, the most plausible emendation is to replace them with him rather than he with they.
Summary: Emend Alma 32:25 to read “let him be in whatsoever circumstances he might”; the earliest extant text, “let them be in whatsoever circumstances he might”, is probably the result of Oliver Cowdery, the scribe in 𝓞, mishearing Joseph Smith’s dictated him as them; the misinterpretation could have occurred as a result of him being pronounced as /ßm/ and the immediately preceding text reading in the plural (“there are some among you which would humble themselves”).