I agree that the other passage outside of the Testimonium Flavium; the "Jesus the brother of James" does not appear to be a forgery, however the line tagged onto the end of it "Who was the christ," almost certainly was. A reference to Jesus the brother of James, or a John the brother of Tom, in no way proves the historical Jesus of the Gospels, let alone that he was the son of God. In the words of biblical Archaeologist Eric Cline:
"Archaeology has not yet been able to shed any direct light on the birth, life, or death of Jesus. That is to say, there is not yet any archaeological evidence for the historical Jesus—or any of the apostles for that matter….However, the failure of biblical archaeologists and pseudo-archaeologists to provide confirmatory evidence of the life of Jesus and the apostles has not been for lack of trying"
Further, there are no records of Jesus the son of Mary and Joseph outside of the religious scriptures, which are not very reliable as they are tainted by the motivation to persuade and convince people to beleive in and convert to, their religion, one religion out of thousands, a thousand to one shot of being true, if you like!
It all comes down to belief and faith and these two things are not proof of anything, but the existence of belief and faith alone!