Kaiser Wilhelm II was not exactly a fan of the Nazi party. After his abdication and all, he spend the rest of his life in exile in the Netherlands. But in a way, he was still watching Germany from the Netherlands. In the early 1930's when Hitler rose to power, he saw that maybe he could restore his throne. A letter written on his behalf was even sent to Hitler, but Hitler ignored it. He had no interest in restoring the German throne, considering the failure it brought Germany.
Flash forward a few more years, Kristallnacht occurs. Kaiser Wilhelm II was appalled by what he saw happening. He saw Hitler as a heartless man and felt Germany was going in the wrong direction. HItler felt that the former Kaiser was Germany's greatest shame since he led Germany through their greatest defeat, also known as World War I. Kaiser Wilhelm II was blamed for the Treaty of Versailles and all the other punishments placed on Germany after the war.
In May 1940, the Nazis invaded the Netherlands. The Kaiser was offered refuge in Britain if he wanted it, but he chose to stay at his home in the Netherlands. There were Nazi guards stationed at his home until his death. The Kaiser's wishes were to not go back to Germany and to be buried on his property. Hitler thought about bringing his funeral to Berlin to make it a symbol but it never happened. The Kasier's wishes were honored and he is still buried on his property to this day.