Maybe, but if the the Tolkien Estate under Christopher T. had had its way, there wouldn't have been any films at all; Jackson and the WB were only allowed to make theirs because J.R.R. sold the adaptation rights to The Hobbit and LotR (but not the rights to Middle-earth as a set of ideas) decades ago. And a year ago, the Tolkien Estate sued WB and Middle-earth Enterprises for $80m, alleging they never had the rights to make those games.
What have they said regarding Tauriel? I'd imagine they aren't pleased. Then again, it's not as though they can do anything about it now....is there?
I don't think Christopher Tolkien is exactly the tweeting sort, and I don't know of any word from the Tolkien estate on that character. Since Tauriel is only a secondary character and is only appearing in an adaptation of a story to which the WB holds this rights, I doubt they'd care to take on the costs of pitting their lawyers against the studios', but that would certainly change in a hurry if the WB were to try announcing a solo spin-off film.
I know they sued over the casino game, but I've not heard anything about them taking any action against War in the North. Would the inclusion of Tauriel really prompt a reprimand from them though? The first LotR movie added the character of Lurtz the orc, an entirely original creation, and no one was bothered.
The article I linked to clearly states they view all the Tolkien-derived video games as illegitimate. Assuming settlement disputes are ongoing, why piss in the fruit punch bowl with a public scolding?
I don't think they're litigious at all really. When you think of the ideas, races, mythology that was first articulated by the LoTR books which have been ripped off hundreds of times since. Big companies raking it in off direct LoTR spinoff is meat and drink to US copyright lawyers. I suspect the estate of JRRT are just being well advised. The funniest posts I saw after the Fellowship was first released were the complaints that it was derivative.