The guy who died wasn't DIYing it.

> The first person known to die as a result of a fecal transplant is a 73-year-old man who developed a fatal infection with antibiotic-resistant bacteria that were in the donor's stool sample.

> News of the man's death surfaced in June; he was one of two patients in separate clinical trials who became ill after receiving fecal transplants from the same donor

https://www.livescience.com/fecal-transplant-death.html