Unfortunately, these documentarians stand in opposition to the preponderance of the evidence. Take the simple fact that 11 of the 12 disciples died for their belief in a Messianic Jesus. Or, attempt to reconcile their assertions with the plethora of extra-biblical sources which reference Jesus Christ, including the revered Jewish historian, Josephus. There is more evidence for the existence of Jesus Christ than there is for many, if not most, historical figures.
If one determines to throw out the historical Jesus on evidential grounds, then one must also throw out most every figure in pre-modern human history and virtually empty University faculty offices around the globe. That is why basically every scholar--including secular historians--agree that the Rabbi named "Jesus of Nazareth" existed in the first century A.D. and had an influential ministry. In fact, questioning the historical existence of Jesus would get you laughed out of almost any university in the world.
The existence of a God can never be proven on this side of eternity, but the existence of Jesus Christ is historically indisputable. It just goes to illustrate the wise words of Mark Twain, who once said, "All you need in life is ignorance and confidence."