The 6%-figure was for a sub-population of victims who received one of the treatments early. There's probably a sub-sub-population of young-adult victims who're in good health and received early treatment who had a near-0% rate, too.

From glancing at Wikipedia's numbers, it seems that the average Ebola victim faces about 50% odds, so this'd improve that to about 29%.

But, with-or-without this treatment, people who receive care, especially early, enjoy better odds than their peers who don't.