Why would you tell the psycho information that will make him really cut you open? Dude mig...

I know. Louise is so dumb sometimes

if he does get disected, I don't think it would be different if he didn't tell the duke? It's to buy him some time because dude's obviously gonna throw a fit after that

Well, provoking him is just gonna get himself disected while he's alive and awake (vivisection). Without provoking him, he has a chance of being dead when the duke starts the disection.