I find it hard to believe that the “fiancée” and all her extended family, living with Duncan while he was exhibiting symptoms, haven’t contracted the disease and are supposedly all through with their quarantine in perfect health.
Only one of the family actually took care of him (and had contact with his waste). She was a nurses aide who used the procedures used in Liberia (gloves, washing thoroughly with bleach after every contact, etc.). Those procedures don’t always work, but they appear to have worked in her case. However, if he had stayed there till his death, they might have been ineffective, because the patient’s fluids become much more toxic around the time of death.