I did miss that, apparently... hmm... but since Olan hasn't heard either of them speaking in their own language yet, I suppose that he would address Iridiel in the dialect native to the highlanders, if such a thing exists. Failing that - if the dialects of their language aren't determined from that - he's liable to speak with no dialect at all, but rather... hmm... English fails me? I have no idea how to describe this in English. The variant of a language one learns in school, the kind of which is exaggeratedly correct and essentially impersonal?