The Deluxe Edition, a tenth anniversary re-release, does include a bonus disc with some internal remixes / B-sides. Like most of these "deluxe" commemorative editions, It incudes the typical ancillary versions that would have been part of the original creative process - things like alternate edits and experimental riffs. It's been out for about 12 years, though, so not sure why you haven't heard it.
Another thing about NIN is that Trent's songs have been out for so long and disseminated so often that how we recall the original music changes. Even after listening to "Closer" hundreds of times, I still misremember the arrangement and hear for the first time elements that were always there.