I think your shutter speed was fine. That wagging finger is moving and the blur lets you know she isn't just pointing it. The expressions of both of their faces is great. You caught the emotions going on in this conversation. I wish you had included enough of the person actually getting the tongue lashing to know what their reaction was.
Thank you for the lesson on Longhorn beetles. The little milkweed beetle is one of my favorites, but I have yet to see one this year. Usually my milkweed is covered with them. All excellent photos.