Meh. Personally, I didn't see a compelling reason to break him out of jail. I can see why some people would want to- why some people would feel it was deserved- but I've never felt anything compelling.
He did a serious wrong- no one disputes this. The Orlesian justice system, as corrupt as it (and the rest of Thedas) is, has a legitimate claim to him- he doesn't dispute this. The Wardens, whatever legal immunity or absolution he might have had as the recruited Reneer, don't have much a claim on him (or vice versa) considering he deliberatly deceived everyone about his identity and association. And, this is important, he desires being accountable and doesn't dispute the legitimacy of the Orlesian system.
If this were a sham trial, or a fake crime, or a railroaded system, or he had a compelling argument that this was an illegitimate thing, I could see breaking him free as an arguably necessary way to achieve some sort of impartial justice. But it's not- the Orlesian justice system and the Game may be corrupt as hell, but they're square on the money in this case, and he knows it, and he accepts it. The system as a whole being corrupt doesn't mean that every instance is, or that more corruption is validated. You don't justify wrongdoing on the basis that everyone else does it.
I don't really believe in spite-justice, where denying someone their wants is the basis for justice, so I don't really see a point in NOT leaving him to his earned circumstances. He can't even claim to being necessary or remarkably advantageous to the Inquisition's 'save the world' agenda.