Cumbersome restoration work

Exploration Stage: Octopus Citadel
From: Violet
Description: We need to find out what the anonymous party who sent the threatening letter used to try to numb the dog's sense of smell. I saw Layden here the other day and saw a broom with something white on it. It smelled like something a dog wouldn't like. Let's look for that broom!
Completed: You found a broom with plaster still on it. I'll check to see if what was on the letter in the example is plaster. At this point, Layden is one of the suspects, but it's possible that he was just trying to reapply the plaster and not the one who tried to blackmail me.