I was wondering if we can take the Death Rattles as written? So night is night, not knight. Reigns is reigns and not rains or reins, etc? Since they're written down by someone who is listening to someone else speaking, there could be confusion there. Then again, they're speaking Alethi, or the local tongue, and being translated to English, so their homonyms would be different. Also, are they always about the future, or can they be about the past?
So, this is a tricky one. I was tempted to go into it during the reigns/rains one--but since there is a follow up, let me see if I can explain it.
You note the mechanism I've said before that I rely upon, that of the idea that the books are done "in translation" from their original tongues. This is to give us another layer of plausibility in the linguistics--but it does introduce a kind of wildcard here in the interpreter. (Who is me.)
I am not against using word usages similar to homonyms as plot points, so long as the characters themselves are capable of making the misunderstanding. (The ending of the Mistborn trilogy involves some of these types of word and definition related issues.)
So you're not wrong to asking questions like this. I use them very sparingly, but I do use them. In that specific case, however, I was not intending there to be confusion.