I'm surprised! My opinion: The Thai (as a Thai, not as a security guard) acted Legally. The foreigner pushed him, provoking a fight. At least according to the laws of many countries, as far as I know.
It seems that the guards have been given legal advice/courses. It's just that in Pattaya lately many Thais are full of hatred towards foreigners and they only need an excuse. Which is what we see here, and happened with British and with man with the owl on the next street.