The hunt felt it necessary to report him to the CAA some weeks earlier for his actions.
I would therefore disagree with your suggestion that prior action is irrelevant as it could be fundamental to the subsequent actions of the pilot and no doubt that will be part of the police investigation of the weeks leading up to the incident.
All in all - it is a mess and somebody lost their life and the police have a responsibility to do their due diligence.
Prior events might give insight to the views/bonhomie of those involved (both hunstsman and pilot), but they don't tell us anything about how 'prop bites man'.
If a man reverses over his kid in the drive, the fact that he bawled out the sprog for not eating his greens an hour earlier would not normally spark a murder investigation!