But if we are not allowed to make any negative judgements about the text based on the translation, then why should we be allowed to make positive judgements based on the translation?
I don't want to put any words in Aristotle's mouth, but my sense is that positive judgments are just as shaky as negative judgments. Certainly from my perspective I consider translations nothing more than a useful heuristic. It is very easy to mistake an artefact of translation, or something inserted by the translator, for what the text actually means. In the translation of a novel or a play this may not be a terribly big deal. In the translation of sacred scripture or meditative practice manuals, it can make a huge difference.
So when it comes to religious literature or studying religious traditions I think it is absolutely essential to learn the original languages. There is really no substitute or way around it. I translate from Tibetan to make material that would otherwise be quite obscure available to a wider audience, but I do not labor under the illusion that reading my translation is any kind of substitute for a direct encounter with the original language, particularly as mediated by the living tradition. Part of the reason why I qualify that by saying "as mediated by the living tradition" is exactly for the reasons Aristotle implies: that the living tradition can answer questions about the texts (meta-textual questions) that the texts themselves cannot answer. It is important to remember that the focus on texts above everything else is a relatively recent and almost exclusively Protestant phenomenon.