An Anonymous Tip

Roberto was no rocket scientist but it didn't take one to put two and two together. Hazel's records had been sealed because she was a minor who was a part of a police investigation. They had to protect her privacy because of her age at the time.

But why wouldn't she have gone to school? Had the Blade hurt her so badly that she was in a coma?

No, that didn't make sense. How would Gold have met her if she was in a coma?

Hazel's trail stopped there (at least in publicly available records) but there was plenty of information on the man who killed her parents. Apparently there was even a book out about him and an episode of a popular true crime TV series.

Roberto was about to dismiss it as useless when he came across Charles Thornton's Wikipedia page. A single word stood out to him. Billy.