Using foreign translations of a novel to solve plot puzzles

The seventh Harry Potter: A fan's questions: "How R A B, the initials of the mysterious character who is also hunting the Dark Lord's soul secrets, changed in the Dutch translation of the novel, where Regulus Black is called Regulus Zwarts and the initials read R A Z. In the Norwegian edition, apparently, Regulus has the surname Svaart, and the initials R A S. In the Finnish translation, I can tell you with knowledge gleaned from wikipedia, Regulus Black is called Regulus Musta, and the initials are R A M."