AnorZaken

I was actually editing the wiki today to clarify this: https://pillarsofeternity.gamepedia.com/At_All_Costs
Short answer: you need to confront him before you kill him.
 
The conversation with Verzano contains a lot of triggers / two "cinematics" (locked interface while characters are moving).
It introduces Pallegina's connection to this whole mess, and Danna will also arrive at the warehouse during the conversation.