Except Kairos was already created, and it was in use by other Ancients in Elpis. It's supposed to be a serious and strictly monitored thing, so you're telling me there's more than one? Or that such a serious thing would be only in Ktsis, at the very top, when it has to be employed by any of the researchers anywhere else? You're telling me it's just is wherever Hermes is, even if he doesn't know whether it's been used or not earlier in Elpis?
Or he just created a new one, and it didn't tax him at all? After he'd already been taxed to his limits in the fight? You'd think such a powerful creation or device or whatever it's supposed to be would come with some weighty cost.
Or you know, the other more obvious problem with the scene. Emet-selch not just blowing Kairos the hell out of the air. Venat reaching out her hand to try and catch Meteion instead of hitting her with her chakrams or idk, multi-tooling her magic sword into a gun and shooting her down. Or the common Holmgang chains all characters get when they need to restrain other characters (Like the ones Hermes employed just a second ago, somehow, weee).
It's actually, really, a terrible scene contrived, artificial, in its every second. People stand with their thumbs up their ass, expositing instead of acting. Shown to seem like they tried their best, only for that to fall apart if you think about the scene for half a minute.