It's not clear at all that the defence witnesses only woke up after the second lot of bangs (only one witness was awake immediately before the first bangs, which the defence argue were gunshots, and she heard nothing before that point). The next-door neighbours woke to a bang, or at least the female half of the couple did, and she woke her husband. They didn't know whether it came from inside or outside the house, so first the husband checked the daughter's room and then the rest of the house, before going back to the bedroom, hearing very loud cries and shouts for help from a man, and calling security at 3:16.
Burger and Johnson, the couple testifying for the prosecution, also called security at 3:16, and heard the second bangs after the call ended, so at about 3:17. The woman's screams and the man shouting for help all happened before that point.
It seems to me that what some witnesses described as "screams" and others described as "very loud cries" were most likely the same thing - Roux got two of the witnesses to demonstrate what they heard (admittedly being somewhat tactical by only asking two of the women!) and it sounded like wailing or shrieking. I wonder if the choice to use one word or another might have been determined by whether they believed at the time they were listening to a man or a woman, given that "screaming" is much more associated with women.
The only odd thing is why the next-door neighbours and the other defence witnesses didn't hear the second bangs, but if they were from the cricket bat, then perhaps that might be explained by them being quieter than the gunshots, by doors/windows being closed, by a poor line of sight to the bathroom, and/or because they were drowned out by the cries which happened at the same time. It's a little odd, in fact, that other witnesses were able to clearly discern screams at the same time as gunshots, since you'd have thought the gunshots would've been loud enough to drown them out (unlike cricket bat blows).
