Sounds like a great initiative from the QPS, I like to think of myself as reasonably tech-savvy, but either the parents weren't in any way "Strict on social media" (I think most were parents would describe themselves as that whether or not they actually were) He was cheating and using Databases that Joe public doesn't have access too, or he has Jedi powers.
Really? You'd be amazed what is easily able to be found on the internet if you try AND know where to look, all publicly accessible. I once found out the name (and a lot more details...) of the CEO of the company that bought out the small business I worked for when it was all hush-hush, no one knows anything about this company, they're just new, etc. etc. Nothing about the company was promoted anywhere, this was before they had a webpage, and they were keeping their cards very close to their chest. All I knew about them was the trading name. And honestly that was one of the easier information digging expeditions I've done to satisfy my own curiosity.
I'm not a hacker. I have no special knowledge or powers. And I can find out a fair bit about someone if I want to... So its not surprising that someone from a relevant police taskforce, or a predator who does this full-time for fun, or a hacker can find out much, much more than I am capable of... because I'm a nobody. LOL.
Also? My parents would have said they were tough on what I got up to on the internet when I was a kid. While I never did anything "bad" by any stretch, they were streets behind my level of computer literacy even when I was in my early teens, and had absolutely no clue what I did or how I did it. I didn't abuse that trust, but some kids will.
Parents - how highly do you rate your computer and internet skills? Because an interested and curious child will learn things quickly and leave you for dead if you don't keep up...