Response time to Flagyl for patient with C. Diff?

This is LO's first bout of C. Diff. Her memory care unit has discharged her to a skilled nursing facility until she no longer tests positive. She was started on Flagyl on Sunday but still experiences multiple BMs daily. Obviously response time is highly variable. I am interested in response times to the antibiotics with C. Diff, not just improvement in symptoms but also how long does it take a 92-year-old to no longer test positive for C. Diff? Loved one has mixed dementia, uncontrolled hyperglycemia and hypercholesterolemia and controlled hypertension. She also has compromised immunity. I know there are no firm answers with this and that C. Diff will likely come back. A time range would be much appreciated for any out there. I just need to know how long her family might expect her to be in skilled nursing assuming the Flagyl is effective. Thanks