I'm admittedly simple minded. If his semen is in the girl, he should die. Let his family choose the labs (10 or 100) that does the tests. If it's his semen, he should die. That won't deter other people but it will certainly deter him. If it's not his, then put him in prison for life because of the child porno.
Until he dies - whether a needle or natural causes -, the victims' family will be paying for his housing, health care, education if he wants, food, legal fees and whatever else he wants through their taxes.