We have a couple of notes for you.
Icecrown Citadel has an attempts counter. When your Heroic attempts counter hits zero, both the Heroic and Normal difficulty end-wing bosses will no longer spawn for the rest of the current week. Thus, in order to fight Putricide, Sindragosa, Blood-Queen, or the Lich King on Normal difficulty, you must have at least one remaining attempt.
Throughout the PTR, Heroic Lord Marrowgar did not properly cast Bone Spike Graveyard during Bone Storm. This has been fixed.
Thank you very much for all of your testing and feedback in the 3.4.3 Public Test Realm! We’re really looking forward to seeing everyone take on ICC later tonight.