At the same time retribution should not be the goal of justice, it should be rehabilitation. I'm totally against incarcerating anyone not posing imminent threat to life for a multitude of reasons but my most selfish is that locking people up is incredibly expensive and I'd rather not spend my tax dollar on it if its not actually protecting me from anything.
US corporate charter exists to exonerate decision makers from personal liability for crimes committed by the company. That absolution of responsibility is in my opinion the primary motivator for having incorporation at all - its a shield explicitly designed to protect you from culpability.
At that a fair judgment would then be something along the lines of - all acting leadership of PG&E or any other corporation using their immunity to be negligent and cause harm must disbar their ownership or face incarceration for being a threat to life. Because they are when they behave like this, at scales that the most deranged mass murderer could only hope to approach.