As for teachers, Mr. China is a graduate student who has just graduated for one year, and the foreign teacher is a foreign teacher in the German Department outside Sichuan. All the teachers teach in German, because the Goethe Institute does not allow Chinese to teach.
It mainly depends on your purpose of learning German. If you are just interested, it is ok to go there for classes. After all, this is the best choice compared with the messy training institutions outside. However, if you plan to go abroad or want to lay a good foundation, I suggest you choose the training course of the German Department outside Sichuan, where the teachers are all German departments. The price is that the latter is more cost-effective.