Hi Kevin
I’ve done exactly this a few times - they do need to be tech enough to plug in the microphone and set record levels etc.
Do you definitely have a PRO licence ? Cubase/Nuendo ships with an LE licence NOT a PRO licence. You need a PRO licence to connect via a LAN. A PRO licence needs to be bought and installed on your Steinberg Elicencer.
There is also a bug where LAN connection fails (i have it on two or three of my cubase/nuendo PCs) so you may be hitting this. It doesn’t use a lot of data, especially if you set the video/audio bandwidth settings to the minimum so you you won’t burn a lot of 4G data if you try to test via that method.
if you use the “ID” login rather than the MySteinberg …I find that simpler YMMV