I agree the CSI/NCIS series are fantastic!
The way i understood last night was that the 'victim' actually killed himself due to his stage4 cancer. But as a proud man he didn't want to go out that way, so his mate = the really creepy CIA bloke, produced a tablet of Sarin, a highly toxic substance that was used by the Germans in the 2nd World War. The idea was that the Germans would be blamed for his death, and therefore no-one would know he killed himself. I think that the book was released to produce a reason as to why the Germans would want to kill him. Not sure about the Son, i think that he was killed because he was the one that had sent the book to CSI to fit them up.
Hope this helps. NCIS tonight! mmMMMM Di Nozzo!