Android Enterprise Device Owned - Reset Device Pin after reboot

[OneController]

Is it possible to reset the pin of a device that has been rebooted/off and I don't know the pin?

I've had devices returned in the past without the pin and it was turned off. My MDMs (yes plural, in the process of switching) can send the commands but the clients do not reply. 

I've been lucky to have device wipes occur after 15 failed attempts due to policy but was wondering if there was another way.

[Moombas]

No as they remain offline until you enter the correct pin. I complained that already to our mdm that direct Boot Support would be needed but not possible right now (at least for our mdm used).

But try recovery Mode if available to wipe the device otherwise you may need to send them to repair wirh the invoice.