Do I have a case against my daughters neurolist who did not inform us of SUDEP, which she died from?..

The literature about this suggest there is no known cause, but the question here is whether your daughter had been diagnosed with epilepsy and treated appropriately.  But from the death alone, it would seem to be without more  facts and reviewing the medical records there is way for any attorney to conclude there even might be negligence by the neurologist.  Obtain the medical records and consult a lawyer.