I think he attempted to explain it by saying there was a lot going on at the time----that was the 2nd baby with an unexplained total collapse within last 20 hours and they were twins.
That is a lot of intense stress and pressure on the medical team. Most of his notes were probably about which emergency medications and treatments were immediately needed. And he would be jotting down vitals and test results too, and anything else coming to mind to save this baby.
He missed making note of the mottling. I don't think that is an earth shattering mistake for an emergency doctor to make. Both babies were brought back from the brink of death, so I do credit the team with that.