Chief Pilots are not able to stop people from doing stupid things, the accident happened due to the fact a young pilot did something stupid and killed himself.
As a Chief Pilot you have to assert yourself but ultimately a person with a CPL should know what can happen from such a stupid action, does a Chief Pilot need to brief him\her specifically on not to do this even though CASA has made the effort to make it LAW.
The coroner did a great job.
Not all GA companies can afford to operate brand new kingairs and provide pilots with 60K package, these pilots are at the early stages of an apprenticeship, therefore crap wages and a large learning curve.