If the father is the real owner, the son was the manager then both stand guilty...
they can be charged accordingly.
However the police no-doubt will not be charged for allowing this place to operate on their patch.
Good, local police allowed this venue to operate knowing that it was illegally operating.
They took the monthly rent and turned a blind-eye to the illegalities.
The owners and police were complicit in this tragedy and any real investigation cannot be done by the local police force.
Zone all you want,
Thais will set-up what they want where they want and the police will take the rent money and turn a blind eye.
That's how Mountain B managed to operate.
I'm only 11 years older than my wife, after 20 years of marriage it's still working out.
The first 5 years we were in England and certainly got the stares, back here in Thailand for the last 15 years not even an odd look.
Maybe it got stuck in soft mud, or couldn't get out, exhaustion set in and it drowned after falling over?
1.5 meters of water is more than deep enough to drown in when you're belly-up.