Well, the Tower of Joy is simply a theory and I wonder of Martin was prepared to tell HBO about any story spoilers before he has finished his story. I am sure it's something that they will work into the plot. It's just going to look different.
Howland Reed was mentioned, so that at least means there's a vague connection if tenuous, to go back to that story arc.
I haven't actually watched
yet. I do wish Martin would finish though. I've been addicted for the best part of my
life to these books.