Regards,
There is there own eyewitness testimony. What other evidence could their possibly be?
Think about it...300 years from now...would there be any forensic grade evidence that any of us existed? Or that on January 1, 2024 you told your friend that you were going to succeed in all of your new years resolution?
You think your electronic media storage devices, or printed photos, or recordings of your voice, or DNA sequence could prove you existed...will that info even survive? Indeed will that information be saved and curated by some of our descendants?...buying futures in Carbonite,eh?
The contemporaries of Jesus saved the most important information about him in the only ways they could. Oral, written, art, changed lives, corporate worship, government laws, words and phrases, Christian organizations, they even argued among themselves over whether their understanding of him was correct.