Further information on this incident is reported in Vice News.
"Two days after the incident, at Koh Samui District Court, 43-year-old Israeli national Eliran Alias, was found guilty of assault and also confessed to his crime. But Alias was handed a one year suspended prison sentence and a 2,500 Thai baht ($70) fine. Despite the court ordering his deportation, sources told VICE News that Alias is still holidaying on Koh Samui, the island next to Kho Pha Ngan."
I find this totally unacceptable. This man has (allegedly) a criminal record back in Israel for assault and violence against women. The girlfriend of the victim had a lucky escape.
A Brit Nearly Died Defending a Woman in a Thai Bar. His Attacker Was Fined $70 (vice.com)