The progression is very rapid, like less than 48 hours from first symptoms to mopping up 15 liters of blood and other juices. Seems quite plausible to me.
It's fast, but I don't think it's quite THAT fast....
"The incubation period for Ebola HF ranges from 2 to 21 days. The onset of illness is abrupt and is characterized by fever, headache, joint and muscle aches, sore throat, and weakness, followed by diarrhea, vomiting, and stomach pain. A rash, red eyes, hiccups and internal and external bleeding may be seen in some patients.
Researchers do not understand why some people are able to recover from Ebola HF and others are not. However, it is known that patients who die usually have not developed a significant immune response to the virus at the time of death."
http://www.cdc.gov/ncidod/dvrd/spb/mnpages/dispages/ebola/qa.htm