Worgen will have to stay in their wolf forms I suppose as that is their true form after the curse and holding a human shape takes some effort and magic. Though it could be explained as worgen curse is a disease not magic so they can shift between human and worgen but nothing else. Druids wont be able to shape shift.
Death knights wont die but their power will be limited to their own strength, it's not cutting magic out it's just severely suppressing it to the point it can't be externalised. So if magic is keeping you alive that's all it will manage to do.
There will be a reason for the warlocks to be pulling people in but I wont be revealing that just yet, if this event goes well I will likely expand on it. I'm tempted to add another rule where pairs and handcuffed together but I may save that for another game