If you're a guest worker in a country with a different culture from yours then I think you need to be very careful here. I don't know what your country/culture of origin is but it sounds like you're not from a southeast Asian country - is that right?
I imagine that two things are going to be important to your Taiwanese colleagues - the importance of socialising children (to the society they live in, which might be quite different from yours) and that everyone concerned can save face. I think you need to be looking for a "win-win" in both those areas if you want to have a positive impact.
How are you planning to approach the discussion on Wednesday that will be with the help of the teacher who has good English? Can you come up with non-confrontational ways to make your point? I've lived in Japan, have travelled in Taiwan, and I found that saying things like, "I'm impressed at how Taiwanese children learn things in such and such a way... I wondered if that could be used also when children can't stop crying" would get a more sympathetic ear than, "This is XXXXXXX."
You might need to bear in mind that "reason" in Taiwan might be different from "reason" in your country of origin. It might be considered more cruel to allow a child to grow up wilful (and therefore be likely to be ostracised) than to address their wilfulness at an early age. They could possibly look at quite young children in a Western country who are out of control, addicted to substances, breaking the law and/or disrespecting their parents and other authority figures, and feel that an emotional, too-liberal approach does a child no favours.
I'm not condoning what you've described. I'm just trying to point out that to make a point that your school colleagues might be receptive to, it would be good to consider where they're coming from and the social context as a whole. That way, you have more chance of striking a chord with those who feel that there's a less brutal way of disciplining/guiding children, that would still work in the culture, than the ones you describe.