Waited an hour, and Pauurc never spawned. I ended up getting the wish quest done the other way. Killing Pauurc would have probably been faster, which was the intention, but it's pointless if his summon can't be started. I think the public events cancel a chance for the encounter. To make sure others don't waste their time, you are better off removing him from the quest. To make up for it, decrease the percentage of Taken bosses needed.