Is it not possible that the jinn may have reached some of the cosmic truths mentioned in the Qur’an before its revelation, given their ability to access the furthest reaches of the heavens and the earth, which might diminish the Qur’an’s purely scientific miraculousness?

Allah revealed the Qur’an for the guidance of humanity. The Companions understood it themselves or through the Prophet’s explanation. Any scientific interpretation must conform to the Arabic language and not contradict the interpretation of the Salaf (pious predecessors). Flaws entered scientific interpretations due to ignorance of [earlier] exegesis and the Arabic language, thus not everything stated therein should be accepted. The jinn were isolated from listening to the Qur’an at the time of its revelation because the heavens were filled with guards and meteors. There is no definitive proof in the Book or the Sunnah that the jinn possess studies or sciences as mentioned in the question; this is an illusion and imagination. Ignorance and lack of knowledge are predominant among the jinn, and their ability to hear the heavens does not necessitate that they possess sciences and studies. One must refrain from asserting or denying anything in this matter, and the validity of prophethood does not depend on such issues.