User blog comment:Nekokokokoko/Slane Theocracy's awareness of Ainz/@comment-80.213.121.95-20150919153419

Good question. There are at least two possibilities:

1. The Windflower scripture (information collectors) could've revived Clementine and Khajiit after their bodies were given to the adventurer's guild. They were chasing them after all. Since Clementine know Momon's identity and Khajiit experienced a 7 tier spell by Narberal who serves Momon, which can only be achieved in New World though magic crystal left by other players, the Slane Theocracy would become wary of Ainz (I believe Momon revealed himself as Ainz when before Clementine died).

2. The Sunlight scripture never returned from Carne Village and the Slane T. were watching Nigun, but they couldn't see anything because of Ainz and when rumours of Ainz came to the capital, they became careful not to oppose a Magic Caster capable of destroying a whole scripture by himself.

I believe there is a combination of the two.