Personally I think the 2 guys are probably guilty, looking at the available evidence.
I am playing 'devils advocate' here.
If the 2 guys in question were led to believe and were shown proof, like ID cards etc, that the girls were, lets say 18, then it would be called 'mitigating circumstances' ?
I would be very surprised if it says in the Thai Penal code, mitigating circumstances are irrelevant? I cannot believe any country's penal code would say that? That is why I believe it would be relevant