Sounds like a good start!

Keep in mind, you are NOT forbidding her to look at the other dog. If she breaks the "Watch Me", that's okay. Immediately start playing "Look at that!" with the trigger. In other words, this is the time to use the "Dog">click>treat method. Repeat this over and over again. Letting her glimpse back and forth between you and the trigger makes her care less and less about the other dog. At that point, you can resume your "Watch Me". Two birds with one stone