Wulfric and Elswyth dont aggro

Me and my friend went into the Wulfric and Elswyth boss fight twice in a row each in a different instance and Wulfric was the only one to aggro after going up to the stage and me using Ferocious Roar. The onlything that might be a reason is that i was in Walking calamity but that is the only thing i had active so i dont know. But the corpse that Elswyth is dancing with also disappears when going into aggro so I dont really know what happens.

Update: After standing around for 2 to 3 mins and writing this post she also aggrod so ig its works? But idk