The roughness of the timbers inclines me to say it is not German

But then again, the Swiss-built church house in Berne Indiana has some very rough timber surfaces, which surprises me (they must have been in a hurry to get it up, and maybe did not have a proper axe for finishing)

Swiss framers at least, and what I understand this is true in many parts of Germany as well, make timbers, often even in barns and granaries, as smooth as they can get them.