There was a Tefl academy in the last city I worked in in zhejiang (not zhuji). It was a smaller city than even zhuji is so the foreign teachers working across the few schools that there were (both public and private) knew each other fairly well. I can honestly say no Tefl teacher had anything nice to say about their experience working there. Here are some of the primary complaints I heard

1. Unfurnished apartment - rooms had a bed and that was it
2. Very low wages - it seemed to differ from teacher to teacher but some were on as little as 2000rmb a month
3. High hours - at least 20 real hours a week. Teachers would also get called to teach classes at the last minute including on days off

The teachers there were all on some kind of internship/course where they would get basic esl teaching certification at the end of a three month period. To me though it seemed much more like pure exploitation of staff given the high hours and low wage they received.

As far as I'm aware that particular school didn't have a license to employ foreigners and therefore couldn't acquire a z visa. I don't know if that was the case with the school in zhuji. More than likely they found someone else to do your job for a significantly lower wage and cost (acquiring the visa, airfare, etc.).