"Take no new action. Without arousing suspicion, arrange to talk to me alone."
He speaks to some people outside the hearing range of the phone, and sends them away. Once alone, "that's quite impossible. I'm in the middle of something rather urgent and if I were to leave everyone would be suspicious about what I had left to do."
"Tell me how long you would have to put me on hold to fix that problem conveniently for me."
"Assuming you have approximately normal standards for convenience, no reasonable amount of time will make that any better." He sounds almost gloating.
"Respond to my curiosity truly, concisely, and completely. Re-answer my previous utterances."
"Is there anything you're hoping I don't know and won't think to ask?"
"Some of the people I sent away are high enough in my Empire to know what this phone means. In minutes at most, people will wonder what the emergency was and why I haven't been informing the appropriate people to help deal with it."
Incidentally, how did you get this number?"
"Krieg. So, without involving any steps or features that would cause attention to fall on him or the nature of my call, invent an emergency which will occupy your people for a couple of hours doing something non-injurious to people and property and tell me your idea."
"I can claim to have received word that some opponents are planning to attack one of our operations, and send some people to defend it. Keeping everybody occupied for hours would require something larger scale, but this would allay suspicion well enough."
"As described, and returning to this call afterwards - promptly - and without arousing suspicion, and without extraneous action, do that."
Kaiser hangs up and leaves the room. He issues some orders, increasing guards at some of the dogfighting arenas the Undersiders are likely to attack. (Just because it's fake doesn't mean it has to be baseless. This might have been worth doing anyway.) Once he's done enough to plausibly be responding to an emergency call, he returns and calls Promise back.
"I want you to, without attracting any irregular attention, travel to New Jersey, get in costume, peacefully turn yourself in to the PRT there, and tell them Promise sent you. Can you think of any defects in this plan that might inconvenience me?"
"The fact that it's strange and unlikely to accomplish whatever the point of New Jersey is. And," he curses himself for thinking too fast "that if you ordered me to do that I could try traveling on foot and rely on my subordinates to find and prevent me."
"Not a clue. It's just sufficiently strange that any plan with that as an important piece becomes questionable."
"The point of New Jersey is to keep you out of the Birdcage, if you're curious. I can skip that part if you prefer."
"You'd have to talk to a lawyer about the efficacy of that plan. But I'm hardly going to object."
"Performing no extraneous actions and drawing no irregular attention, expeditiously but not in such a hurry as to confuse uninvolved bystanders, proceed with the described plan."