Brothers in arms: Novigrad (The Witcher 3: Wild Hunt)

Stuck quest: Brothers in arms: Novigrad step Help Roche with Bianca (immediately hangs to talk to Distroy). On the Internet write that it is necessary to go for this quest an eye for an Eye and then you can talk with Roche for help in the battle against Hunting, but it seems like, judging by the log, I have passed, and the Rocher says nothing, if you come to him in the cave, there is no dialogue. Bianca there in the cave and only responds Yes? by pressing E.
What to do with it? You can only go to Dykstra, but he will send and say that their cases fully, and then the quest the Brothers disappears and Roche and not to invite.