She is discussing the things the witnesses heard. She says that some of the noises that were interpreted as the gunshots, but were actually the bat.
She says some of the others could have been asleep and missed some sounds.
She discusses Berger and Johnson was correctly criticised as unreliable, but were unfairly criticised as making nearly identical statements, as they didn't write these themselves; they just related them to Von Aard who has his own style. He was not called to say why he used the words he did, so we cannot use that against the witnesses. They were not dishonest, they had no interest. They didn't enjoy giving evidence. They were reluctant, but only came forward after the bail application. They were, however, mistaken in what they heard.
However, this does not mean that the entirety of their evidence should be discarded. Not every error effects his credibility (the witnesses). The court has to evaluate all the details and consider how many contradictions there are, and how relevant they are to the case.