Antibiotic Failure - Is the Initial Diagnosis a Correct One?

The most common causes are the sgram positive and gram negatives, which the vanco mison and suphopem should have covered. So i'm thinking about what would we be missing with a coverage? And then I think about the treatment that kind of goes with the bug. Do we have on the right antibiotics? Was there some reason why they couldn't get the antibiotics? Or maybe for some reason not getting into the tissue due to not having appropriate penetration.? There's definitely a lot to think about, and i'm on the edge of my seat to hear more.