It is NOT a traditional German soup, it is something the Bavarians (from the Kingdom of Bavaria) who emigrated to Russia in the 16 and 1700s brought to the USA.
IT is also not Knoephla,that word originated from the German word knuepfen (pinch) and abknuepfen (to pinch off). In the now German Bavaria they still pinch noodle dough off in small pieces instead of cutting it. As an old German (came to the US at age 31 in 1958) I have never heard of a soup that had both broth and milk as the liquid ingredient. There is nothing similar in my German cookbooks dating from 1874 to the 1960s.