give us a different address, we have sent units to Germany many times without problems, but of course there is always a chance where custom do not believe this is just a engineering sample.
I see your ticket, just reply with new address and we'll try again.
Added a note with a different shipping address to the support ticket. Please send the unit dismounted without the PSU and the TP-Link. Or make absolutely clear it's and why it's a engineering sample. As I understood the customs officer there was no document at all, just the device.
Thank you