Jack offered me a job at a language center in Chongqing city, but contract details looked fishy, containing a "probationary period" clause, and a start date different from the one we agreed upon.

I have solid and direct contact with a handful of reputable Chinese universities and institutes, and will proceed with them on into the hiring stage if I see fit. Direct contact is the way to go in this regard, so do take great care and do not give it all away.

There are many Jacks out there, and there will be many more. Tread carefully. An individual in his living room with a laptop can cause tremendous grief.

What caused you to be lured by the recruiter 'Jack' from reputable direct-hire Chinese educational establishments to a private Chinese language center in one of China's ovens?

Was it the extra cash, or was it your options having been greatly reduced on account of your age?

I put it to you that recruiters like Jack can arrange probable employment at state educational establishments for you were you to initially demand that.

Next time, you are seeking employment, try direct hire first. If that is unsuccessful, use a couple of recruiters, but insist on public schools/colleges/universities. Should they try to lure you into the private sector, shed them fast.