Interesting point of reference - for whatever reason A Nightmare on Elm Street seems to be a bit tricky to license. Dead by Daylight which has more horror licenses than you can shake a stick at couldn't get the Original NOES. They resorted to the remake.
Halloween, and anything done by John Carpenter, is a relative breeze to acquire and he's on record saying he'll pretty much let anyone roll with his franchises, and music, if they ask permission.
The Texas Chainsaw Massacre, or at least the first film and it's characters also seem to be pretty easy to pick-up, at least at the moment. There's a Texas Chainsaw game that was just released, a new entry in the franchise, and quite a few films in recent history.
Point is, based on recent history, it's not surprising to me that A Nightmare on Elm Street didn't come easy. My personal theory, based on the fact that we've only seen him in original Elm Street stories at the event, and I believe in Japan, is that the character is much easier to get than the film franchise.