How to enable shutting down a device from Lockdown menu?

Hi everyone, I am wondering how to enable shutting down a device from the lockdown menu, without using the power button. We have several customers using Samsung Active Tab 3 tablets. They have the weird additional function button, but that means the usual power button doesn't work as a power button and turning it off requires additional actions that not always work. So my goal is to make a Lockdown screen icon, that will shut down the device. These are enterprise enrollments. I managed to setup a restart script using the Custom action in lockdown and a script in a cmd file on the device. But unfortunately I found out, that while the restart script works, shutdown and turnoff scripts already don't work anymore.Does anyone have any other idea? Maybe using the Action: command, or Intent: or whatever...