There's no hypothesis or theory stated here, he's merely showing a collection of information to make people understand that something has been happening in our solar system. The truth is no one could possibly know, and anyone claiming to is simply lying. All we can do is make predictions on what may happen based on what we know, the more information we have and the more we know and understand the more accurate the prediction. Kinda how predicting the weather is never accurate because we don't understand how it all works and therefore can never predict anything with total accuracy.

No on is asking you to agree or believe this guy or anyone else, he even states something to that effect at the start, simply that you look at the information and think for yourself.