I've wondered about that, and I came up with an explanation that seems to make sense. She needed someone to hear the shot, so that the time of death would be known with certainty, which would strengthen her alibi. What do you think?

Yes, that makes sense completely. Puts the time of death at the exact time she was supposedly making the changeover. Still risky, but makes sense. Thanks Clay! By the way, you have the best name - Make Me a Perfect Murder my favorite episode.

thanks, I like your name too. Season 7 for the win.