Yeah, I'm not disagreeing with you. It's probable that this means that they're either not really part of the Gotei 13 as I assume the Commander-General would have ordered them to assist in Fake Karakura, or that they don't have anyone powerful enough to assist (I.E., no one of Lt. or higher equivalent strength) and the Commander-General didn't want to just get Kido Corp members killed for no reason.