So Narnia is planning to kill two birds with one stone. And I think Narnia can kill Iruma and frame Shida and so that Shida won't talk, I'll kill her too. Although the target is Shida not Iruma, at least from the perspective of the other members of the border police, except Narnia.
And everyone in the Walker park arc remembered Shida. And Narnia wasn't the main person responsible for introducing Atori and Shida to Babyls, maybe even Wett and Miki to Leiji's academy. My logic would be that Naberius Narnia should be questioned too, he just introduced them there.
And on another note, they say that first impressions count.
1. The first impression Shida made: He saved Iruma from a slum-like neighborhood in the demon world.
2. First impression made by Naberius Narnia alias Fenrir: He told Iruma who is a human how people should be eliminated on sight.
In conclusion Iruma has more trust in Shida even though Iruma doesn't know that she is from a terrorist organization she made a good impression on Irums and Narnia doesn't inspire trust in Iruma because he kind of threatened him with death, which would make him a terrorist, which could mean that Narnia made a bad/bad impression on Iruma.
So I understand that this is Baal's way of firing someone from his own organization. I don't know if Narnia before getting angry would try to pet Kalego's familiar form to see how fluffy it is.