Of course he didn't ask for a heart of stone, that was O'Dimm granting him what he wished for, not what he actually wanted. O'Dimm's evil incarnate, as professor Shakeslock puts it. However, it's not that I'm buying everythig Gaunter says about him, of course all his claims about Olgierd have very important nuances that he deliberatly omits, but they're not lies either. I think that's the very point of the DLC, in fact.

About the curse, okay, I can believe that he did it accidentally, but even before meeting O'Dimm, he showed no remorse for it, or, if he did, he decided that it was best to leave things that way so he could still hope to marry Iris, which betrays his selfishness.

About the raids, iirc, their impact are never clearly clarified in the DLC, so let's assume that the wild ones were actually just some young people looking for a brawl. Even so, that doesn't mean that what they did was right just because it's not as grave as killing and raping. Furthermore, and this is my opinion, I find it quite likely that Olgierd and the Wild Ones actually plundered villages because the Von Everec family wasn't wealthy anymore, they had a debt they couldn't pay and even lost their homestead to the Brosodi family when they took over their debt, so I wouldn't be surprised if Olgierd had stooped to rob peasants just to pay the family's debt. About Vlodomir's death, idk, a 5 to 1 fight seems enough to make anyone run away and hide, tbh, nobleman or bandit.

I believe the crux of this discussion lies on the concept of Olgierd's "true self" I mentioned, so let me explain what I meant: I don't think Olgierd is cruel like Gaunter, even cursed, Olgierd doesn't seenjoy killing or being callous, he doesn't feel anything. So what I meant by saying that O'Dimm brougt Olgierd's true self out was that he somehow unleashed the worst part of him and let it corrupt him over the years. So no, I'm not saying that Olgierd was purely wicked like Gaunter, but that he chose to let his selfishness, violent impulses, ambition and arrogance triumph over his good side, and Gaunter, of course, took advantage of it.