Story-line confusion (SPOILERS)

There is something I’m not quite understanding, and I’m sure we will all figure it out after the last Forerunner book is released. What I don’t get, is when you meet the Librarian, she mentions they locked the Didact in Requiem. We all know the Didact eventually activates the Halo array. But how can they lock him up if he kills everything in the galaxy? The only speculation I can say is that the Ur-Didact, after committing his atrocities with the Promethean Knights and what not, is locked up and then Bornsteller Didact is the one who activates the Halo Array. But even that doesn’t make sense because I’m pretty sure it is stated somewhere that the Ur-Didact, the one in Halo 4, is the one who activates the Array. Speaking of the Librarian, isn’t the fragments of 343 Guilty Spark supposed to be searching for her? The books and the games seem to be contradicting each other in certain areas, and we all usually agree the canon set by the games is the ultimate one and any contradictions in made BY the books should be ignored. I would just like some clarity.

[deleted]

Ur is halo 4, so bornstellar has to be the one who activated it.

Also, I notice that the description of the new Forerunner book details an ancient evil that is discovered by Ur and the Librarian. Now, Ur-Didact has always hated the humans, but I wonder if this “ancient evil” pushes him even further into insanity.