I am told often enough times by the clergy and religious laymen and other theist here that it is a fact that there is difference between evidence and proof and that evidence and proof are not the same thing, which is true of course.
Speaking for myself, I have never claimed to have been able to "prove" a single one of my "assertions" or any conclusions that I may have reached with only the scant "evidence" available to me from the four Gospels, which ultimately ends with an hypothetical, an idea or simply an educated guess when it comes to the four gospels and the life and times of Christ and his very short ministry.
It appears at times that the theist will throw out the accusation of "you are unable to prove anything that you have concluded". To which my answer is, 'yes, you are correct. I can no more prove that Jesus even existed than you can'. So the question of proof here is beside the point.
Take for instance the claim that Jesus was king of the Jews, while all the time only assuming Jesus existed, the only available evidence from the four gospels points to the conclusion that he was but it is not proof. Jesus himself never claims to be king at all. All claims of kingship appear to come from elsewhere, including from his enemies: Pilate and the head board of the cross for instance, and Herod's "fear". The wise men in search of he that was "born King of the Jews" and their royal gifts. And from this scant evidence Christians world wide have themselves asserted that the title "King of the Jews" is an established fact.
So we see that is all the researcher has at his disposal is evidence and not proof and evidence can only suggest greater on less possibilities and plausibility.
One can only draw on, assess, survey, interpret it and draw a conclusion i.e. such as a sequence of events is more likely to have happened than others. And from there the matter should becomes one of commons sense.
That other accusation of "speculation", something I also admit to, goes towards creating the hypotheses. Indeed a hypothesis rest on speculation.
Did Jesus and or his disciples have a hand in John the Baptists death? Hypothetically it is a plausible possibility that they may have going by the evidence.
Of the 83,680 words that are in the four gospels Jesus is said to have spoken only less than a third which are not a lot considering those words can be read in a matter of hours. And neither is it a lot of evidence either.