The daily is worth your trouble, as it rewards 160 Tomes of Aphorism, and we've detailed everything you can do at the new Tomestone Vendor with that currency, too.
Once you've done that and unlocked both Smileton and The Stigma Dreamscape, you'll need to complete them before Expert Roulette becomes available. Players must recomplete this duty to unlock Duty Roulette: Mentor. the duty 'the Praetorium' is no longer counted as complete. Being level 90 is not enough, and you won't be able to find those NPCs until your story ends are all tied up. Scenario Mode, which allowed players to progress through main scenario dungeons from Patch 5.0 through 6.1 with a party of NPC allies, has now been incorporated into the Duty Support system.
You can't do either of the above without completing the final Main Scenario Quest from version 6.0, Endwalker. What are the Expert Roulette Dungeon requirements? You'll unlock The Stigma Dreamscape once you're able to interact with the other quest NPC, N-7000. Jamingway will take you to Ultima Thule, where you chase him down two more times. You'll need to accept the quest, ' Where No Loporrit Has Gone Before,' and head to Labyrinthos (X:14.4, Y:27.6) to speak to the Loporrit again. The Stigma Dreamscape quest begins by speaking to Jammingway in Old Sharlayan (X:10.9, Y:13.4).