Board Thread:False Info and Speculative Discussion/@comment-4091815-20170918183706/@comment-26879545-20170925201507

I'm going to assume they both died because:

A) Kate was shot with yellow Wolfsbane and it wouldn't make sense for her to live when it was established in the same episode that it would have killed Scott if Derek didn't burn the wound.

and

B) Kate obviously wasn't going to show any mercy to Gerard after he shot-to-kill her. Also he's a dick and would deserve it.