Can I flash a (google looping) nexus 9 factory image remotely without debugging activated?

[AC Question]

I have a nexus 9 that continually loops the google start logo and nothing else. I can get into the bootloader mode but all options (including factory reset) just result in the google logo looping. The device does has not been debugger enabled (the bit where you tap a button seven times etc). I can get my pc to connect to the device, but anything I try either directly with sdk or wugs just results in the message that my device is locked (not the bootloader). E.g. I try "fastboot oem unlock" and it tells me the device is locked. I think I'm screwed. Does anyone have any ideas how to get past this and flash a factory image to image and rescue the thing?!?!?