the groomer had said she didn't think that was very good for a dog (to be forced to wear a muzzle to be forced in turn to do something it doesn't like).
IMO, you need to find a new groomer. Of course your dog isn't going to see her as an alpha being if she doesn't think dogs should have to do anything they don't like. Please. If we never made our dogs do anything they didn't like, they would at best be completely unmanagable and at worst be dead. And they most certainly would never be bathed or groomed! I think you need to find a groomer with a little more common sense about dogs.