The relationship between Tongji and Germany can't be found in domestic universities, so can you speak Tongji German?

Junior students of German Department can basically go to Germany for exchange, and students will not lose their experience and knowledge.

As for employment, it depends more on personal ability. If you can only speak German, you will not be very competitive in any school, because language is only a tool after all.

So from the perspective of employment, if you want to improve your competitiveness, you'd better learn more skills, such as minoring and taking more courses.