You are overlooking the fact the conversation was cut short.
The call was made based on the soc evidence: blood stains to flooring/lack of, casings, distance of shots, trajectories and wound tracks. The totality of this evidence supports SC opening fire on June in bed and NB leaving the handset on the kitchen worktop to go upstairs where he sustains the two facial gunshot wounds on the little landing stairs just preceding the entrance to the main bedroom.
Agree the call was cut short. Ekeven words. You can sat that again.
Agree June was shot in bed.
You are not a SOC expert. The prosecution case is Nevill was shot in bed. The DPP, jury & appeal courts agree.