You're right. It sounds like "vakkere". I wonder if it is intentional.
I looked up "The Two Towers" to see the Norwegian name and apparently it is "To tårn" If I am not wrong that means "Two Towers" though, so would "The Two Towers" be "De to tårnene"? If not, why is that?
Yes, it would. "To tårn" just makes for a more catchy title than the direct translation.