@ SirChet - in first playthrough I did look into the dead corpse of Jack and participated in choosing which patient should be healed. After that I did fight the pirates.
In the following play I focused more on fighting itself than solving murder quest and let it sit almost till the end of gameplay. Same with the patients treated by Evelyn.
After digging up the body of Jack - I still had no trigger on Zixzax. He showed up after I decided which patient should be healed.
