The situation is not unique. I have been in China for several years, here with a Chinese wife. I arrived in Kunming from my old city on an 'L' visa, it was December and I had not been working due to the academic year starting in Oct. I have just changed to a 'Z'. I have also had 'F' visas.

The 'Z' visa is often used as leverage by Chinese employers. But you don't have to play their silly games.

If you work for a state school they are less likely to do this as they know it is hard to recruit teachers they like (better the devil you know).
If you work for an English training centre, some will fiddle with the pennies, but if they kids like you they are reluctant to let you go, but they will still try to leverage.

If you do decide to leave, as long as you find a new job and get a new contract and 'Z' visa before the old one expires, no problem. This can be renewed in Kunming.
If you can't find a new job in time then transferring to an 'L' family is easy, but the pain in the butt is that you will have to go to Hong Kong if you get a new 'Z' visa.

In short 'Z' to 'Z' visa is easy and can be done locally. 'Z' to 'L' is easy and can be done locally. But 'other' to 'Z' requires a trip to HK (or other country outside mainland PRC.

You don't need to mess around with an 'F' visa which is what most agents will offer, and which is technically illegal to use for employment.

PS I used to drink a lot of Yunnan Hong

I have had some nice Chinese wine given to me. But I would not pay the 150-250rmb price myself.

There was also a recent scandal about Yunnan Hong. This wine is made from old world grapes imported about 200 years ago. Some growers were adding industrial alcohol to boost alcohol content. Having said that some European growers were guilty of this in the 70s, and again in the 80s.

I am not a fine wine connoisseur, but I would rather pay <50 RMB for an imported gulping wine that tastes OK than some of the local wine of a similar price. I once had a bottle of Changhyu for 60 RMB that I found undrinkable, and I will drink almost anything.

I avoid English corners as I have found they consist of (as described above) lots of Chinese, a few foreigners, and lots of introductions. I can see why some people only go once every few months as I find them exhausting.

If the English corner has a theme for the evening they work much better. But as most people don't organise anything, and others could not organise there way out of a paper bag, the default conversation starts with "Nice to meet you, where are you from...?"

Additionally, English corner is not really a good place to practice your Chinese. They are not really meant for that.

Sorry if this sounds negative, but that is why I don't participate.

My reason for posting?

Perhaps this information may help those who run English corners to avoid this major pitfall.

The advice from most police forces is to just give an armed person what they want.

The original post did mention abduction however, I am not sure many people would just give up a child, or themselves.