Great stuff. So we know the kernel is fine. Funny that this is true for most of those new devices but we are still not sure why hand off from iPXE to the kernel does not work nicely.
Please try as George suggested to see if our client kernel is able to see and use your USB NIC. But if it does not, then this is a different issue as the initial black screen after the FOG menu. Not sure which one we should address first. Well let’s see. Hopefully you see if getting an IP.
So if you get some time you might want to test this ipxe.efi file with debugging for kernel image loading enabled (DEBUG=image_cmd). There might be lots of messages (in colors) scrolling past. Or maybe nothing. We will see how this behaves on your device. Please take a picture or video if you can (readable test is important!).