"What are your conclusions about the facts they claim in the video? Is it reasonable and worth considering? Can it resolve debates about different religions?"
My conclusion, arrived at a long time before seeing this video, is that the world is full of deception, and one has to work quite hard to see through it all.
Any organisation that sets up Superiors to intercede between man and God seems blatantly misguided and deceptive. God is available to any and all of us. I don't believe he favours those who wear expensive clothes, gold jewelry, and who claim to be holier than other men.
God is a concept of goodness. God almost transcends definition. He is everything that evil (or the devil) is not. He is a very simple concept really, until he becomes institutionalised in the form of religeon. Religeon seems to me to just set up systems of power, gatekeeping, and revenue raising. It seems to have very little relevance to the relationship between God and man.
Why do all these religeons seem to have so much in common? Perhaps it is just because they all use a well proven formula that works wonderfully to gain revenue, power, and glory for their various hierarchies.