The problem is there was no "trafficking ring." If you read the article it says:

'Throughout the operational period, officers and undercover detectives placed ads on websites and apps which are commonly sought out by suspects seeking illegal sex acts with children," read a portion of a Phoenix police statement.'

So there was no trafficking until the cops pretended to be traffickers.

These people are still sick, but they were arrested for crimes that - although they were willing to commit - they didn't actually commit because a child was never involved. It's a soft form of entrapment, yet even the article title (and I'm sure the police press release) will make it sound like they took down some big, bad organization when they actually didn't.