Wait and see, personally I think it sounds like you've dealt with her quite firmly, and the 'booking an escort for my husband' line sounds like a woman panicking, not one ready to start a war. If any more comes of it, my next move would be to grass her up to AW. She clearly has too much time on her hands!
In a way, she's doing you a favour - decent clients will suss the fake feedback just like you have, and all the tight-fisted ones will go to her, leaving you with the cream of the crop.
I understand completely why it's winding you up, though! Why can't people just live and let live? Anyone can make money in this business if they put the work in, there's no need to try and take other girls down. If someone was doing similar but better than me, I'd be looking for inspiration from them, not trying to make petty fake bookings! I don't get the logic of that, unless she books
tons of appointments, forever, it's not really going to affect your business to any great extent anyway. Balls to her