Here in Alma 26:14, while copying from 𝓞 into 𝓟, Oliver Cowdery accidentally omitted the demonstrative these from “these our brethren”. This kind of construction, “these our X”, is fairly frequent in the original text, occurring seven times; in fact, in four of these cases (each marked below with an asterisk), the following noun is brethren, just like originally here in Alma 26:14:
Clearly, there is nothing inappropriate about the original reading “these our brethren” in Alma 26:14.
Summary: Restore in Alma 26:14 the demonstrative these in “these our brethren”, the reading of the original manuscript.