I'm not quite sure that any of these secular investigations into cover ups by bishops have resulted in any bishops in any country being held accountable for their decisions regarding abusers.  Pell is in Australia for abuse allegations against himself, not that he covered up abuse allegations.  I think the Vatican is well aware of the distinction and will let Pell make or break his own case. 

 I have seen very little in the way of Vatican sanctions against any bishop for covering up abuse until Fynn, and he was convicted in a secular court before the Vatican responded. Pope Francis is not the pope who will seriously take 'bishop accountability' in any real manner.  He is too much the religious authoritarian to do that and this is evidenced by his own track record when it came to abusive priests in his own Archdiocese in Argentina.