I could be wrong and would be happy to be so but it seems like this to me:

If someone did a few months of house arrest for "pleading guilty to solicitation of prostitution involving a minor" it would be incredibly easy for that person to say - whoops, she said she was 25 and then they threw the book at me." And not terribly unreasonable for someone to take him at his word on that.

The real crime is that the prosecutors massively under charged him for doing an insane gigantic awful pedophile recruitment ring. No one really knew that til a long time later.