What do you think of the Most Holy Monastery (vaticancatholique.com)?

I am really curious, I would like to know what you think about the Sedevacant Benedictine monastery, Monastery of the Most Holy Family, and its teachings. The only thing I want is for you to justify what you say with evidence that proves your point of view. For example, you cannot say: the Diamond brothers are heretics without providing concrete evidence. Ditto for the opposite.