The only legal scenario that comes to mind about him not going to trial is if someone in Remand does him in. Then, it would be difficult to hold a trial.
He could suddenly, and without warning, go completely off his rocker, and be clinically diagnosed as permanently insane, and there would still be a trial, except he would be relieved of being expected to instruct his solicitor and a panel of Barristers would be selected to represent his interests at that trial. He would be presented at the trial, probably via ZOOM in that case, but if he can stand, and be quiet, he goes to the court.
He must be present. In whatever capacity is seen applicable.
If he pleads guilty, at trial even the morning of the trial, the matter smoothly pivots to the sentencing component of the consequence. The judge, in his infinite wisdom, lays out, in exquisite detail the mechanics of the crime, the subsequent investigation and it's findings, any input or statement by the accused, the case the defence put up, in a precis, ,the case the prosecutor put up, precis, and then explains, in gold plated detail how he arrived at the sentence he is going to impose. And then he announces the sentence.
This part.. the Summing Up of the case, and the sentencing, videoed, it will be on the Supreme Court,Victoria Website , but for a very short time, 1/2 day tops. You have to be on your toes, and catch it then because it disappears into the archives. But , if it's like other Supreme Court cases, it is certainly worth the view, if only to get a nice big dose of English as she should be spoke.