Official comment
Yes you can use the RB-DMX1 with the CDJ-3000 in PRO DJ LINK LIGHTING mode! No need for performance mode, just make sure the players are linked, open rekordbox to LIGHTING and click on the PRO DJ LINK LIGHTING tab at the top. You'll see this page:
All of the controls in blue are in auto mode, but you can click into them for manual controls. I don't have any decks connected now, but you would see the decks and their status in the top left.