I liked the way she realised that while Johnson/Burger took 4-5 mins and Mr Nhlengethwa around the same, the timeline left the Stipps hearing what they genuinely thought were a woman's "terrified" and "petrified" screams, of someone "in fear of her life" and "out of her mind with fear" for 13 minutes BEFORE calling for help. A scenario that would leave the Stipps as not very nice people imo, so it was imo clear that there had to be an error in their timings.