MC fears a corrective force from the original plot, but at the same time recognizes that if there is one it would have killed him in someway as he did make the story stray.
MC is not thinking very clearly for the mess he is in, overthinking details.
He never heard of the marquis in game, the dude possibly died in the stampede, or is just one of the surviving nobles that made the kingdom resist after it, but of course a normal game wouldn't describe every single detail of every single person that died in the stampede or helping characters that are never seen in the game.
If there is a corrective force is very weak or mostly acting on the hero actions.
Note even how MC interacted with the hero by saving him from being raped and kidnapped, is unlikely that a event like that would have been skipped in the game, MC should know about it, and until then he acted as a background character so is actions shouldnt have changed a event like that.
There is even the fact of the kingdom ignoring artifacts and dungeons, this is a case of the universe wa smade 5 minutes ago and the whole history until then didn't truly happen.
