LuvThailand . . . the gentleman who ended up in the calaboose was probably ~ as they say ~ simply "in the wrong place...".
I don't believe he was charged with the underage thing, but the whole thing ended up being thouroughly complicated by his attempting to pay a "bribe" to the cops and/or the judge. Whether this worked or not I have no idea, but the end result was some months in jail for him and then being released which cost him a lot of money.

The reason Aquarius was raided in the first place, I believe, had to do with boys from Burma being illegally employed there rather than it being an underage issue.
The Farang just happened to be in a room (quite naked) with a young man. Unfortunately for him the news reporters "just happened" to also be there at the time & the photos were plastered all over the morning papers.