Here 𝓞 is not extant for the end of the relative clause “in whatsoever place they should be”, but spacing between extant fragments of 𝓞 indicates that the original text for the relative clause probably read “in whatsoever place they should be in”—that is, with an in at the end as well as at the beginning of the relative clause. The transcript of 𝓞, as provided in volume 1 of the critical text, assumes as much:
go forth preaching the word of Go(d )
IN WHATSOEVER PLACE THEY SHOULD BE IN
in any part of their land yea he sent a ( ) DECREE AMONG THEM THAT THEY SHOULD
Without the in, there would be excessive gapping between the words in the lacuna.
As discussed under 2 Nephi 2:22, there are three established instances in the original text of the relative clause with the form “in whatsoever location one is in”—that is, in all three cases, the relative clause both begins and ends with in:
The first one is extant in 𝓟, but not in 𝓞; the two others are extant in 𝓞. Another example involving whatsoever also had the in at both the beginning and ending of the relative clause:
In this case, the 1837 edition deleted the in at the end of the relative clause, probably accidentally. As pointed out by David Calabro (personal communication), there is one example involving whatsoever where there is no in at the end of the relative clause:
But we should also note that for this passage the verb be is omitted, which means that the ellipsis of the in at the end of the relative clause is expected. 𝓞 is not extant for the end of the relative clause in Alma 32:25, but spacing between extant fragments shows that there is no room for be in in 𝓞 except by supralinear insertion. (For discussion of the conflict in number between them and he in Alma 32:25, see under that passage.) Basically, in whatsoever-clauses the preposition in is repeated at the end of the clause providing the verb is not ellipted. These examples suggest that here in Alma 23:1, the original text read with an in both at the beginning and at the end of the relative clause, thus “in whatsoever place they should be in”.
Evidence elsewhere shows that when Oliver Cowdery copied from 𝓞 into 𝓟, he sometimes deleted short words at the ends of lines (see the discussion and examples under Alma 11:21). And the fact that here in Alma 23:1 the next line of 𝓞 also began with an in (that is, “in any part of their land”) may have facilitated the loss of the in at the end of the relative clause when 𝓞 was copied into 𝓟. Another in can follow the final in of the relative clause, as in the example from Alma 34:38: “and worship God in whatsoever place ye may be in / in spirit and in truth”. Based on the spacing between extant fragments of 𝓞, it is quite likely that here in Alma 23:1 the original manuscript read “preaching the word of God in whatsoever place they should be in / in any part of their land”; all similar relative clauses involving whatsoever support in both at the beginning and end of “in whatsoever place they should be in”.
Summary: Emend Alma 23:1 so that the relative clause both begins and ends with in: “in whatsoever place they should be in”; similar usage elsewhere in the text and spacing between extant fragments of 𝓞 support the occurrence of the repeated in in Alma 23:1.