As you already stated in your first post, "If you submit a document in any language other than English, the document must be accompanied by a full and complete English translation. The translator must certify that the translation is accurate and he or she is competent to translate from that language to English". There's nothing in there about the translator being certified by anybody or any organization. Yes, anybody fluent in both languages, also competent and willing, can certify a translation, even if they are the author of what is being translated.