Sangoma 60 appliance, require import details

First off, this is a slightly unusual request - I’m aware of this.
We have preconfigured one of these units and shipped it in a small server cabinet with other hardware, to a site in China.
The China customs office is refusing to release the hardware as it does not have a CCC certificate. Ok, lesson learned, we should have worked this out beforehand.

I’m being told that if we tell them some technical details of the unit, they will try to clear it. They’re simply asking for: “electric current, voltage, power, etc.” and yes, that’s a direct quote.

So, who can I speak to? I need to resolve this or… well, actually I don’t know what the ‘or’ is. I’d guess they just burn it and cook smores over the flames.

Open to any suggestions here.
Thanks.