I know nothing about it, but if it's been doing well around the foundation of that house, it ought to do ok in the south. Can you get some cuttings from the owners?

Sorbaria sorbifolia does great in zone 7 Maryland. They have heat and humidity just like us, and it does fine. I have been wanting to try it too. It blooms in the heat of the summer which is a plus.

I had S. arborea a few years ago. I didn't plant it in a sunny enough location and it became lanky and unattractive. I pulled it up in favor of a Clethra barbinervis. I wish I had tried it elsewhere because I really did like the foliage. It was a beautiful dark red when first emerging, much like the evergreen Clematis(armandii).