Very interesting news indeed. And very different from the narrative as we knew it thus far, including from Wilhelmina's own memoires.
The Dutch public channel made a 30 min. documentary about it, in which they also visit Burg Hohenzollern with Prince Georg Friedrich, who talks about his characteristic Prussian nose:
https://www.npostart.nl/andere-tijden/10-11-2018/VPWON_1283698
The episode is called 'A Royal Lie'.
It is surprising that the late Prof. Fasseur did not find more details about the matter, as Prof. de Graaf mainly used only the archives of the Hohenzollern's in Huis Doorn which would have been open to him as well. It was thought that Fasseur was allowed access to the Royal Archives because Beatrix could rely on him being discreet about sensitive issues. His book about the break down of Juliana and Bernhards marriage was heavily criticized. One wonders if he chose not to investigate this particular episode further on purpose. Not that the issue would have been sensitive or particulary damaging for the RF in the late 1990s when his biographies were published.
Although some conclusions seem quickly made - all monarchs were related to 'Onkel Willy', many more closely than Wilhelmina, the case she makes is rather persuiasive. The fondness for the emperor, which she discovered in Wilhelmina, seems based on a visit to Berlin when Wilhelmina was 10 y/o. De Graaf claims that Wilhelm was a sort of paternal figure to the young queen, which is new to me as well (not that he saw himself as a mentor but that Queen Emma actively searched for it).
Still, if he was such a strong father figure it is even more surprising that Wilhelmina did not marry one of the Hohenzollern princes (grandsons of Prince Albrecht and Pss Marianne of The Netherlands IIRC). De Graaf says that Wilhelmina never met the Emperor after the war because of reasons of state, but that she still had warm feelings for him. It is completely different from what has been said up to now, which was that she behaved coldly towards Wilhelm. If there truly was so much coldness it would have been odd that she allowed her mother, husband daughter and son-in-law to pay visits to Doorn.
Wilhelmina's willingness to host a Peace conference in The Hague is surprising for reasons stated in posts above. And perhaps ironic considering how much she fumed against the two peace conferences and the opening of the peace palace (& Tsar Nicholas II who proposed it all) as she found it a humiliation for the country. In 1919 German officials wanted to publish information about the failed peace conference, which was prevented by minister van Karnebeek and the Queen.
A pro-German stance of Queen Wilhelmina in WWI is also new though De Graaf softens the language in the tv program and talks about the 'two hearts' of Queen Wilhelmina -one for neutrality and one for family/friends- that are in conflict in the summer of 1918.
De Graaf gives a lot of convincing details that the authorities knew what was going to happen, for example how the village doctor of Amerongen was notified in advance of Wilhelm's flight, a file of the French secret service officer in The Hague talking about '40 suitcases' with which Wilhelm was supposed to travel to The Netherlands, the visits of Dutch and German diplomats to Amerongen in the summer etc etc. She also puts the visit of general Van Heutz -a great favorite of Wilhelmina- to the German headquarters in November 1918 in a more probable light. The official explanation that he was there to observe manouevers was never likely & was widely doubted by historians.
De Graaf claims that while revolutions raged in Europe, the Dutch queen still had actual power which she used not for the good of the country but for personal reasons. I am not sure if that is fair. Even the British later came around and thought it best if the emperor stayed in exile in The Netherlands. A trial of a (former)monarch would have encouraged revolutionary feelings in Britain it was thought, when it was clear that monarchs are ordinary people too. Up to now it was also maintained that a big role of Wilhelm's welcome was that the Netherlands was a neutral country and to prove that neutrality it could not pick sides. Welcoming a conquered neighbor would not be in conflict of neutrality but an expression of it.
Although it is not surprising that the court & government preferred to keep the peace conference and the Dutch involvement in Wilhelms flight to the Netherlands quiet at the time & esp. after WWII, it is surprising that it took this long to be challenged & revealed. Queen Wilhelmina's word was believed 'on her blue eyes' -as De Graaf says. It is clear that she must have known about the Emperor's arrival but as Hans Goedkoop says in the documentary: it is not proven that she took the initiative for it, a 'smoking gun' is missing from the large pile of sources that have been discovered.
