It is just an example of the contrapositive. See the notes: If one is a Jedi, then one is a Force user. Athena is not a Force user. Therefore, Athena is not a Jedi.

"In the first argument, premise 2 identifies a member, Athena, and says that she fails the necessary condition, i.e., she doesn't use the Force, placing her outside the superset. The conclusion follows that therefore Athena must also fail the sufficient condition, i.e., she must be outside the subset and not be a Jedi"

I think it's because "the bacteria" serves as a modifier to fail (predicate). What we're discussing is that the antibiotics fail, and I am assuming that in this case "the bacteria" is not central to the kernel of the sentence. What do they fail to do? Kill. Kill what? Bacteria. Bacteria from what? The kind that lives deep in wounds. But sometimes it does get confusing. There are things I wouldn't consider objects that are considered to be objects and vice versa.