Is the Hadith that interprets the word "Bismi" in "Bismillahi Ar-Rahmani Ar-Rahim" as the Ba’ signifying the splendor of Allah, the Sin signifying the loftiness of Allah, and the Mim signifying the dominion of Allah, a prophetic Hadith from the Messenger of Allah, may Allah bless him and grant him peace?

The Hadith was not found to be مرفوع (directly attributed) to the Prophet, peace and blessings be upon him, in the reliable Sunnah books. However, Ibn Abi Hatim mentioned it in his Tafsir as موقوف (attributed to a Companion or Successor), specifically to Al-Dahhak, who was a Tabi'i (Successor). A Hadith that is موقوف to a Tabi'i is considered مقطوع (disconnected) and does not serve as a proof in such matters, even if it were authentic; so what then if it is not authentic?