The fact that ancient texts are unearthed with differing accounts of who Jesus was is not really surprising or noteworthy at this point. There are many MANY historical texts and accounts from that time. And is it surprising that those who compiled the bible left books out that say Jesus wasn't the son of God, but merely a man, were left out? The Christians who cannonized the bible believed Jesus was God and worship him as such, so yeah a book that says he was just a prophet is not going to make the cut of what they define as holy scripture.
These books that show up shouldn't be viewed as some "Oh No! This disproves the gospel! The book of Luke is full of baloney!" but more like "Looks like people have disagreed on who Jesus is for thousands of years. Interesting to see how certain scholars and historians took the time to document those ideas."