How can I boot an Xbox One demo unit into kiosk mode?

If you are a shop owner, make a usb with a file called MSXB_Kiosk.

No file extension. It will work, but you need a shop disc to play game demos.

Kiosk units are the properly of Microsoft just like Dev kits are and many not be sold.

Hello Moonlancer, this is Manuela. I'm an Independent Advisor and community user like you, ready to assist with this.
Not a Microsoft employee.

I would like to clarify that we’re not capable of assisting with console modifications. It is against the community guidelines.

Your understanding is appreciated.

Yes, it’s actually the property of GameStop. Sort of their fault for dumping it outside .

If there are no games on the USB stick that puts the console into Kiosk mode, then you don't have games to run in Kiosk mode. Simple as that.

I'd assume you (or the person from which you got the Kiosk) "faked" the USB stick to get the console into Kiosk mode by adding a fake file on the USB stick?

If it is an actual Xbox Kiosk that you legitimately got, you need to contact Microsoft public relations to get Demo discs with proper game demos on it.

EDIT: After a bit of research: It really seems that you can only use actual Demo discs on your console in Kiosk mode. You probably can not install "regular" games on the console and then put it in Lockdown mode with the USB stick.

EDIT2: After finding
this page here, I assume the following:

The USB stick is only a key to lock the console in Kiosk mode. It requires you to have installed the Demos from a demo disc previously.

The game attract videos you see come from a different device in the back of the kiosk with an additional USB stick.

So unless you also get a demo disc, you can't play games on that kiosk unit in lockdown mode.