In this passage we have three types of changes that were introduced into the 1841 British edition. The first and third of these types were never transmitted into the subsequent LDS edition, but the second one was. We consider each one in turn.
First, we have the change to the plural forms yourselves and hearts, as if Alma were speaking to more than one son: “suffer not yourselves to be led away ... suffer not the devil to lead away your hearts” (the 1841 text). This plural reading was, of course, reversed in the following 1849 LDS edition.
Second, the 1841 typesetter changed the that-clause to an infinitive clause, thus leading to a change from “suffer not that the devil lead away your heart” to “suffer not the devil to lead away your hearts” (the 1841 text). This change in clausal construction seems to have been influenced by the use of the infinitive clause in the preceding sentence, which also begins with suffer not (“suffer not yourself to be led away by any vain or foolish thing”). So originally here in Alma 39:11 we have variation between the two clausal types. Elsewhere in the text, there are two more examples of the form “suffer not that S”, where S is a finite clause:
For these two examples, the finite verb of the that-clause is the modal shall, whereas in Alma 39:11 we have in the that-clause the infinitival (that is, subjunctive) form of the verb, lead. The critical text will restore the original text here in Alma 39:11: “suffer not that the devil lead away your heart again after those wicked harlots”.
The third type of change in Alma 39:11 is the loss of the preposition in in the last clause, changing “they would not believe in my words” to “they would not believe my words”. Elsewhere in the text, there are examples of both possibilities, with three occurrences of “believe in my words” and two of “believe my words”:
Either reading is possible, so we follow the earliest textual sources in Alma 39:11 and maintain the preposition in (“they would not believe in my words”).
Summary: Restore the original text in Alma 39:11, with its finite that-clause after suffer (“suffer not that the devil lead away your heart again”); also maintain the singular number for yourself and heart as well as the preposition in (in the final clause, “they would not believe in my words”).