Are there any material historical proofs that establish the existence of the Prophet Muhammad (peace be upon him) for non-Muslims who do not believe in the Qur’an?

Denying the historical existence of the Prophet Muhammad, peace and blessings be upon him, is a fallacy, as historical facts are proven by reports and various relics, not by direct observation. The certain historical evidences of his existence are numerous, including the Holy Quran, the prophetic relics in Mecca and Medina, the continuous chains of transmission (isnād) for his hadiths and biography, the existence of the noble Companions, the widespread manuscripts and documents, Islamic and non-Islamic history books that addressed his call and state, major historical events, his letters to kings, the continuously transmitted history of the Islamic world, the thousands of families descended from his noble lineage, and his miracles, foremost among them the Holy Quran. These evidences leave no room for doubt about his historical existence.