Rachel,
You are very welcome, I know how heart wrenching this is. My cousin was in the same situation, we couldn't keep her off of drugs. Her brother was a Miami-Dade narcotics detective, he did everything in his power to help her, as did I as a nurse. Finally, she was found dead from an overdose in a sleazy motel in the Coconut Grove.
I hope you can get to Las Vegas and get her the help she needs. I go back and forth to Vegas a lot from CA and know that there is a low tolerance to homelessness and drugs, it shouldn't be too hard to get her the help she needs, especially as she is mentally incompetent to make her own decisions.