I had these show up in the recent past, and while I ended up reluctantly doing them anyway, other mentors will want to leave right away... and I honestly don't blame them.
You can't skip the cutscenes, the dungeons are still laughably broken and really easy to complete at this point due to lingering exploits and a lack of item level synchronization, and it generally feels like someone is punished more for still choosing to finish it rather than abandon the instance; that harms new players too since they'll now have to either immediately wait for other Main Scenario Roulette participants or new players, or start without a full party. I'll stick with the instances, but many mentors understandably won't want to. The Praetorium can last up to an hour sometimes, if you start counting from when initial cutscenes play and not strictly the timer, and you don't get a major tome bonus since you're not playing it via the Main Scenario Roulette.
When I see those pop up, I have to wonder exactly what it is that Square Enix wants me to help with that's not properly explained or surprisingly difficult with those two dungeons, especially when I end up being placed in the instances while none of the other players are new due to the lack of a slight poetics reward boost message. Instead, I feel like I do the same amount of tedious waiting as in the Main Scenario Roulette but without getting the same major experience or tomes boost, and many mentors will end up just leaving right away since the Duty Finder penalty is shorter than the length of the dungeon, plus they can just go do other things while waiting for that penalty to end.
Those dungeons should either be removed from the Mentor Roulette, give better roulette bonuses for people who end up being added to it via Mentor Roulette rather than Main Scenario Roulette... or these could both become obsolete requests by Square Enix just doing what should've been done with those two instances last expansion and rework them into single-player story instances.
Can someone also explain to me from a design perspective why Mentor Roulette will sometimes toss me into those two instances even when the game detects that nobody is new to the instance? Who exactly am I helping then? I want to help newer players out, not do cutscene-heavy dungeons with significantly worse rewards while also not really helping teach dungeon mechanics to anybody.