Howling:"Silence" in the Library?

So it's the first/last River story and this season is very River heavy. Now I really want to rewatch it to see if there is any areas that the Silence could have been worked in. Maybe Moffat planned things this far in advance or maybe he had the idea later, but with the title and the River/Silence prominence this season it could serve as a way to bring the River backstory full circle and provide some explanation as well.

Gouge