It's probably a coincidence; I've only seen the first few episodes of the first season.
These coincidences happen all the time in D&D and storytelling. For example, since 1997 our campaign world has been a sunless winter where feudal knights plot politics and the only heat and light in the long winter comes from a strange red comet that cycles the world as the sun once did.
In 2004, my wife and I were browsing the shelves at Borders. She picked up "A Clash of Kings" and read the back cover copy--which was essentially what I just summarized above. I hadn't read George R.R. Martin at that point, but I was kind of perturbed that he was stealing my stuff.
As I write this, I realize that this Encounters season is also about the world shrouded in a sunless darkness, and though I designed part of this season, the outline and concept were presented to me beforehand.
So what I'm saying is: common themes, common story elements yo.
I will eventually get back to Sons of Anarchy.
Ron Perlman is a god
"Rachel" from Mad Men is in it
Katey Sagal rules--though it was really weird watching Sons and Futurama at the same time. Good-weird.
Is there a section of the session named "Sons of Nesme?"
I don't have the module in front of me, but it's certainly not in my draft.