(Photographs courtesy of Nick Bawden.)
As I describe elsewhere on this website, personnel from both the Allies and the Central Powers were interned in Switzerland. Those chosen were prisoners of war who, though sick or badly wounded, might still be capable of military work and could therefore make fit soldiers available for serving at the frontline if they were repatriated. Internment in Switzerland would aid their recovery without furthering the enemy’s war effort. The photograph above shows German officers at Davos railway station, probably just after arriving there on their way to the internment camp. As you can tell from their headgear, they came from a variety of army units, as well as from the Imperial German Navy.
Saxony is a German state, which includes the cities of Leipzig and Dresden. Prince Johann George was the younger brother of the then king of Saxony, who chose to abdicate at the end of the First World War.
Although it was not all fun and games, being an internee was not the same as being a prisoner of war. Internees were often permitted to engage with local Swiss population.
It isn't completely clear what is happening here, but if I had to make an educated guess I would say that Major Abt was being repatriated to Germany because it was judged that his recovery from wounds (or mental strain) would take so long that he could not be employed for military purposes. The building behind the men might even be the one in which the internees lived.
Furka Pass is a high mountain pass in south-central Switzerland, a considerable distance away from Davos.