Well, not exactly "nothing".
Once Maura said the bone was a fetal clavicle, and the murderer knew he could be identified that way, it was obvious that the murderer had to be in a DNA database. That was when I realized the "golfer" had done it. He and his wife were touting the bone marrow database at the top of the show.
All Jane and her crew needed to do, once the database id'ed him, was to scour the internet for photos that linked him to that club the bouncer worked at.
I did like the fact that they brought up Paddy's impending trial.