I have the cure!
Painkillers. I have phantom pains from severe spinal cord injury and after years of suffering, a dr finally gave me Oxycontin. It worked immediately!
I know its not RLS, but my wife get RLS real real bad and nothing worked for her either. I thought it was just my pain rubbing off on her like "sympathy pains". Iron didn't work. I finally gave her a painkiller and within 1 hour, her RLS was COMPLETELY GONE! It worked. IT ALWAYS WORKS!
We now know that her sore, tight, worn out lower back is the cause for her RLS. for the same reason I get pain: the lower back scar tissue applies pressure to the nerves, making them irritated. When we meet someone with RLS, we ask about their lower back, and most do have back issues. I think this is the cause, which seems to simple to be true and overlooked, but the results are clear.
The hard part is now obtaining pain killers from your dr. Hers wont give them to her. I do.