If using the NXS2, when browsing, It typically displays the title of the track in the first column and the second column can be set per the user's preference: key, comment, artist, etc. I have mine setup to comment. I've had the camelot key inserted into this field.
When searching, it depends on what query you entered in the search field (artist vs. track title).
While it's great you organized your file library on your hard drive, none of that is really relevant with regards to Rekordbox and the way navigation works. You'll need to create playlists/folder within Rekordbox if you want to organize your library in a manner that allows you to easily navigate through everything using a CDJ.
This all assumes that you've imported and analysed your music in Rekordbox prior to using your tracks on a CDJ, wither via Link Export or Exporting the music/playlists to a properly formatted drive.
If this is all new to you, I would strongly encourage you to view some tutorials on Rekordbox track preparation (and software usage) as well as CDJ usage. The best scenario would be for you get your hands on a CDJ (or XDJ) so you can familiarize yourself with everything, nothing beats hands-on practice.