They might have to. I saw your other post, about who owns the rights, and I've also seen some of that as a LotROnline player. There might be other issues becaus

They might have to. I saw your other post, about who owns the rights, and I've also seen some of that as a LotROnline player. There might be other issues because of the movies, if MEE/SZC gave the studios exclusive (or time-exclusive) rights to the characters and settings. That still leaves a lot, though. Angmar and Dol Guldur are only alluded to in the books, not visited, which makes them Tolkien Estate territory. Gondor's a bit trickier. The kin-strife involved characters not in LotR, but the settings might be contentious. A lot depends on the specific details or the contracts among the various parties, which we don't know.