I like the let it go approach. Asking the decorator if there was something said in her presence, could create discomfort. Recreates more drama, than necessary. If there's topics that involve work related changes, it's one thing. Too many cooks in the kitchen, can ruin the soup.
I find that talking while the hands move, is a more suitable kitchen discussion. One of the cooks I admire working with the most, runs her kitchen in just that way. And when I worked a specific station with a specific coworker, in my early years, it was exactly what each of us did, naturally. We sure did bring in some serious numbers, during those years.