Be careful while chelating with DMSA. It is known to exacerbate candida. It also is tricky when chelating cadmium. This will be appropriate for you. http://en.wikipedia.org/wiki/Itai-itai_disease
It would be much more helpful to see her hair test and know the prechelation symptom list.
Chills. Is she getting enough selenium? Low thyroid or a combo of it and low adrenals too?
I assume she is on at least Cutler's essential supplements .