Everything about this screams 'meth'. The guy didn't just freak out, rip up a toilet, and then beat himself to death. My bet would be that he freaked out and snapped at someone and they beat him/robbed the place - knowing that drugs and/or money were hidden in the toilet, or it was premeditated and they tried to rob him but he fought back.
Tony seems like a meth-head, too. He likely wants to deny this, remain in the country and also not end up with his head smashed in, so he's probably just trying to parrot the Thai narrative to make this all go away.