VIC Application of Criminal Law on Felony Murder?

In the State of Victoria, three men (A, B, C) aged in their mid-late 20s invaded a man's (D's) home during the night brandishing a shotgun and baseball bat. Somehow that man scared them out and chased them around to the front garden where a physical altercation took place and a shotgun discharged, shooting A in the chest at point blank range.

B & C rushed A into the car and sped to the hospital where they removed A from the car, leaving him outside the hospital on the main road. B covered his face and ran to the emergency doors, alerting staff his friend had been shot, was laying on the pavement outside and needed urgent attention now! Before running away.

Sadly, A was already dead when police found his body. Autopsy shows the double barrel 12 gauge shotgun discharged 2 shells directly into his chest and exited his back in an upward direction. His internal organs were obliterated and medical experts agree his chances for survival at any stage, were zero.

I would really appreciate any thoughts, opinions and also the application of criminal law in relation to the legal outcome for a crime such as this. Any potential charges, which laws are relevant and possible penalties at sentencing.

Felony murder laws have changed so I assume the replacement will be something like 3A murder and joint criminal enterprise - type relevance.