The protagonist who's looked into all this is an American historian and writer called Dan Gibson. He went to the Middle East in 1979 and has lived in Jordan, Yemen and the United Arab Emirates, as well as travelling all over the Arabian Peninsula many times. He has conducted his research for almost 40 years (when this film, The Sacred City, was made). I don't know if he's Muslim or not, but the ideas he presents certainly stack up. I feel to protect him and his family with white light, as I feel he is a type of warrior spirit who is bringing truth to one of the main religions of today, and I daresay that is a dangerous game. In the end, it is not a truth that will harm the revelations that Mohamed received. It is more like a twisted skein of rope, where some truths got waylaid, because of simple human greed / need / confusion / or prioritizing what was best for a particular sect at a particular historical timeframe.
I think truth is going to need to trickle out about all types of religions, in a major way, and of course we are right in the timeline for this to happen. Thanks to brave and adventurous souls!