The NPC is no longer available once the 0.6 version launched. The NPC rewards was to compensate the save wipe. The rewards are Skin Tickets to immediatly unlock a skin (once available), all skins are unlockable in-game though. the Skin Ticket just skips the requirement for the skin of choice. I hopce that makes sense. So even if you missed the NPC you can still get all the skins by unlocking them in-game.