As far as where she was raised, I believe most Au Ra were around Doma/Orthad areas. ((Not sure if spelled correctly))
Also, the 2nd thing would be her last name. Xaela, like Miqo'te have a naming convention most follow. Attached is what those names could be. Also, even SE says themselves, there are countless other tribes out there who are not named, so maybe she could be one of those.
Other then that, I myself don't see much wrong with your concept. Although if she was raised in Doma/Orthad, Au Ra would of been a highly common race, so the fear of them being related to dragons would of been almost minimal.