M.B.
Delicious-n-fit in Plano is an entirely gluten free bakery/restaurant: www.delicious-n-fit.com
She can make basic decorated cakes in house and she uses the designs from Cakes Amore for fancier items (they're still baked in house to avoid the cross contamination).
And, they taste great! They are made from scratch and taste far better than any that you'll find at any of the other places you've already called. They are closed on Sun. and Mon., but you may get a response via email if you have specific questions before then.
She can also make cakes that are free of other allergens, as well as sugar free. She'll make you exactly what you need. Take a look at the cakes on the website - they're under the "shopping" button on the top right of the webpage.