It truly is the sort of thing that one should seek medical attention for, I agree. However, at the time she had no insurance and the oral vancomycin that had been prescribed to her was going to be $1,500 per prescription fill, and as you said, it probably wouldn't have helped too much -- C. diff creates spores that tend to outlive most treatments, lending to its 'difficile' name. It was a scary time, but she got very, very lucky.
We've been off-handedly following news articles about treatments like this one, and this pill is an excellent advancement of treatments. Here's hoping no-one else had to go through what she did.