See the detailed discussion of her crimes against the disabled on our forum
No. It's handy but doesn't really mitigate a disability even for a person with social issues who feels uncomfortable excusing themselves when they need to leave the room. Why? Because they still must be able to excuse themselves, they just use the dog as the excuse. Actually no training is required. Most dogs will react positively when you ask them if they need to go out. Even if the dog doesn't naturally react, you can still act like he gave you some subtle signal, or just plain say you need to potty your dog without coming up with a justification for doing so. The potty excuse, even when trained, is a bonus, not a task. However, a person with anxiety that severe would definitely have need of several real tasks so it's no barrier to such a person being able to have a service dog who coincidentally can be used as an excuse to get out of awkward situations.