I too would agree with both you and Ken. Sarah needs to think about how to pick a moodle hosting company or Moodle Partner. As you have noted, what started out with one issue "backing up a database" has really ended up with "how do I install moodle correctly?" I am (still) guessing that Sarah used some form of one-click install, or her provider got her started. Still don't know.
I am sorry that I could not help here.