Completed Pestilence tonight. My resolution was similar to Phenom:
Knocked out watchman, picked barn, pickpocketed letter from bandit. (I did not initiate Pestilence up to this point).
Following morning, I paid my dues for behaving like a scoundrel, started Pestilence, helped the woman bury her husband, got Vincents will, went to Sasau to turn in will and get help from monastery. Returned to Merhojed, handed out remedy, went and completed Questions and Answers.
returned to Sasau and waited a few days (until status of Pestilence changed to: wait and see if the remedy works). At this point I changed the resolution to 1920 x 1080 (from 2560 x 1440) and waited a few more days. There was no cutscene, nor a crash. I returned to Merhojed, spoke to the Bailiff and completed the quest.