What's with the bones?

So in the third chapter of the book, a shady lawyer appears who just happened to work with Metzer and is being chased by these shady characters. Apparently, Oepida's ex-boyfriend had payed for bones and the client of this man had not been payed for it.  When I heard, I immediately thought that this would be the mystery of the story. As it turns out, it's really just a red herring and the man is just a McGuffin meant to lead Oepida to Trystero. However, what I am confused on is why Trystero is the word that attracted Oepida and why she never followed up with the bones story. After all, it does feel like an unsolved case, and it even isn't even brought up again. Even Mitzer is hardly touched after the third chapter, making me wonder why did we spend an entire chapter developing the romance of the two in the first place.