But the thing in the published version was also in the other translation. Cain says "Even my father doesn't know about this place", and two pages later, his father is saying, "Cain! I told you never to come down here!"
This ups the odds that it's the author.
Ah well. The rereading's a lot of fun, and the emotional wave builds very nicely. Also, I'm reading them all together, and all in order. The English translations were published in a weird order, the first 2 or 3 volumes of Godchild coming out before volume one of Cain, when the five volumes of Cain precede the 8 volumes of Godchild. And then, it alternated -- one Cain, one Godchild, repeat until the Cain volumes were all out, then the last couple volumes of Godchild.
It's much easier to appreciate the development of the story when I'm re-reading and when all the books are in the right order.