I think the sentence for aggravated kidnapping is life--but that could either be the state sentence or the federal sentence--or both. He and his honey, Wanda, have a good chance of being tried in Utah AND federally for a variety of charges--and he could be looking at charges in California & possibly Nevada as well. If the sentences run concurrently, he's going to be in for quite some time.
I do think that Wanda Barzee has a better chance of a lighter sentence IF she gets out of his sphere of influence AND testifies against him. She may not do that--and if that's the case, she's going to go down with him.
Either way, sane or insane, he'll be put away for a long time.
I suppose, given what he had written, that he planned to keep on kidnapping little girls until his harem was full. Prison would not be kind to him.