DD has eczema - we were referred to the general paediatric clinic, but they had a weekly dermatology clinic, with a specialist, so maybe your hospital has something similar, and that is what you have been referred to.
Is her eczema crusty and a bit yellow? If so, it is infected and she may need anti-biotics or a cream with anti-biotics in it for a little while.
Different creams work for different people, so I'm afraid it you will probably have to keep trying different ones for a bit. Make sure that you are not using anything with lanolin in it - E45 is definitely out, it is not recommended for eczema. My DD reacted to anything with paraffin in it, I think that is fairly common. We don't use any bath oils, just epiderm as a soap substitute, and only 1 or 2 baths a week.
She gets a mild steroid cream on her face where it is worst every day, not ideal, but better than raw crusty itchy skin.
The dermatologist said that they don't recommend changing diets as eczema is cyclical and it is very difficult to know whether a flare up is caused by particular foods. We worked it out though as when we introduced solids, DD was very obviously ill when she ate dairy (like a scene from the exorcist.) Her skin seems much better now she has a dairy free diet.