Mr. Monk and the Three Julies - S6-E13
Other mistake: When Natalie sits down with Randy eating ice cream, she's says "vanilla fudge, my favorite." But the carton is labeled "chocolate." Plus Randy says he got it out of her freezer, so she would know she bought just regular chocolate ice cream.
Answer: The two men are trying to work out a secret deal between them without involving the union, which means the workers' interests aren't being represented and defeats the whole purpose of a union. The mayor would lose labor's support and Cusack's union troubles would just be starting.
Captain Defenestrator