The birth of The Cleric may have disrupted the odds
On my most recent playthrough when i got to Urth he said that his will had a 4/5 chance of working out and coming true. But when he was dying he saw the odds for that happening start to shift, he then mentions how it was a esoteric event that lead to the change in odds. I then remembered that the cleric was born about 7 months after Urth died and because there are only 10 months in a year so pregnancy may be shorter its possible that Ragns conception happened the same time Urth died. I think its possible that these two things are related and Ragns conception lead to a esoteric event that changed the odds in Urths will. I don't know if its possible or not but it is something to think about