You are all neglecting what should be the main focus here, "Lady Colin Campbell’ is not a reputable historian. She writes tabloid style books, often with some scandalous, fabricated hook, which she uses in publicity rounds... much like the title she acquired for a brief minute, through a failed marriage to a Lord in the 70s.
What we do know, for a fact, is that Q. Mary was a submissive, and had no political influence as far as anyone can tell. It is not logical to assume that her grievances would override her dominant husband, who viewed himself as having a strong bond with his cousin, the Tsar.
The fact is George V's decision was a political one, made out of fear, historians have a tendency to give a few lines to support his decision, 'it was a tricky time' etc, but I don't think a lot of people grasp just how unstable and cataclysmic WWI was. It fundamentally shook society, and changed the political order and British society as a whole, no one saw it coming in 1914, but in 1917, George was absolutely correct in thinking it could 'bring down the House' as it had in Russia, and would in Germany.
It was an act of fear, but not an illogical one.
It unfortunate that it haunts his legacy, and a bit unfair. Nicholas II & Alexandra had multiple opportunities to help themselves, and their people. For over a decade, close relatives, friends, trusted courtiers and ministers, begged, petitioned and worked covertly to assist them, the fact was they were obstinate and deluded, a dangerous mix... this is was condemned them, not the fact that their cousin, aborted their one of their final chances.