There was supposedly only a 4% probability of that after updating on his god's warning.  Keltham doesn't know if the read here is that his god understood which exact leap of wild guessing he'd make, or if Cheliax is dumb enough to fake the attack he indicated being nervous about in the most blatant way possible.  He can't trust his truthspell, now that he knows what Fake Being Enchanted actually does, he knows exactly how easy it would be for a fourth-circle cleric to defeat, and they didn't mention that to him even if Carissa said (honestly?) that she didn't recognize the spell -

"Pilar's dead.  Is that permanent when somebody does it using a horrible-looking sharp thing."

There was supposedly only a 4% probability of that happening this quickly even after updating on his god's warning.  Keltham doesn't know if the read here is that his god understood which exact leap of wild guessing he'd make, or if Cheliax is dumb enough to fake the attack he indicated being nervous about in the most blatant way possible.  He can't trust his truthspell, now that he knows what Fake Being Enchanted actually does, he knows exactly how easy it would be for a fourth-circle cleric to defeat, and they didn't mention that to him even if Carissa said (honestly?) that she didn't recognize the spell -

"Pilar's dead.  Is that permanent when somebody does it using a horrible-looking sharp thing."