While you communicator might be able to communicate with dogs, there's no way of telling if she's for real or is a fake. People who do these types of things often give generic statements that would apply to most people. You could hide something right in front of your dog and see if the dog tells the communicator where it is!
Hopefully she knows a little something about dog training and will be able to tell you things that build up the dog’s confidence. A dog that doesn't understand the rules and doesn't have a job, is going to have little confidence. Cesar thinks a good way to give a dog confidence is to take her for walks, and I think it can change a dog's personality. The walk is seen as a job by the dog, and the job helps the dog find its place in the world. Your dog has been bounced from place to place and probably doesn't feel like she can really trust humans. If you were seeing a child psychologist, only a few of them would be concerned of the "why's" the child is behaving the way they are behaving, most would be concerned with the behavior and work directly with that. Same with a dog, you don't really need to know the whys, just work with the behavior. I personaly would rather have time with a good dog trainer.