I haven't "done" China since diagnosis, and nor have I done much Chinese food since, aside from home made stir fries etc. Unfortunately, Chinese food is probably one of the trickier cuisines for managing by diet alone, not only because of their reliance upon rice and noodles as "fillers", but also because of their application of the Yin/Yan principles, whereby they usually have multiple flavours in any dish. By that I mean they will balance salt and sweet, salt and sour and so on.
For me, this would be a case of picking the best, or as likely, the probably/possibly/here's hoping the best available at any given time. If you're able to have the meat or fish element served separately, then adding your own sauce or accompaniments, that might make it easier to work out where the sugary bits are and sort of manage the starches. I say sort of, because they'll often have cornflour in sauces for thickening and so on.
But, I would also be asking myself how long I'm in this environment and how often these circumstances are going to be repeated. In reality, if your best efforts, whilst still feeling engaged, joining in and fed(!) aren't as good as you might do at home, then it's unlikely to have a long term effect. Eating nothing, being starving and not enjoying a rather special trip will be longer lasting (in your mind) than a few days off-plan.
I'm certainly not saying to throw yourself face first into the biggest bowl of noodles you can fine, or to mainline on sweet and sour pork balls, but it would be pretty awful to go on such a great trip and come home feeling cheated. I doubt that would be great for your mood, and could well impact on your travelling companion(s). So just do the best you can.
I don't know if it might be helpful, but the following link is a bilingual chinese "menu". It won't tell you what's in every dish, or their carb count, but it looks like it could be useful working out what has pork, fish or whatever in it.:
http://www.travelchinaguide.com/intro/cuisine_drink/food-menu/ (Sliced pork in hot chilli oil has started my tasted buts twitching, and it's only 8am here!)
Have a wonderful trip. Your more usual wagon will be in UK awaiting your return.