In the Purge the Unclean Campaign, Shades of Twilight scenario there's a statement:

If the Liber Daempnoca escaped (...) it will turn up once again in the Baron Hopes.

But I see no mention of the book in the third adventure. Does anyone know anything about it, or it just avoided my attention?

I've noticed that as well.

Also, barring capture by the DE, how does such a blatantly evil and dangerous book end up back in the hand of heretics and mutants?

Personally I have a plan for the book that will have my players questioning everything they think they know.

Well I'm in a bit of a trouble, 'cuz the adventure mentioned that it will reappear, the sergeant escaped with the book. I'm GM-ing Baron Hopes now, and the players are desperate to get it back. But there is absolutely no mention of it :S