There’s quite a bit of debate within the psych world about just exactly how sociopathy, psychopathy, and other related names and ideas come about. Some believe it’s wholly biological and genetic, some think it’s created through environmental causes (being traumatized, mainly), some think it’s some combo of the two. It’s also important to distinguish between behaviors, and motives – all we know in this case is what this man did, not why he did it. It’s possible that he feels no remorse about his actions, but it’s also possible that he is deeply tormented by past trauma, and this is a way of him trying to take control, or this is him reenacting something that happened to him in an attempt to make sense of it, or… With only this much info, there’s no way to know why he did it. There are a myriad of reasons for this type of behavior, and sociopathy/psychopathy is really only one or two of those reasons.
As for cures and treatment, whether or not you think it can be treated depends greatly upon what you think causes it. It’s further complicated by the fact that, while there has been some successful treatment (and no, that successful treatment is not castration, real or chemical), the very nature of the disorder makes the people with it less likely than normal to seek and and be invested in treatment.
Couple points: 1) your daughter is way more likely to be raped by someone she knows already, not a stranger and 2) locking your daughter up is actually a great way to traumatize the shit out of her and make it more likely that she would act in a similar fashion.