I work as a network engineer at a university we get our students to register their devices via mac address see:
has this been resolved or is it likely yet or do we advise our students just not to purchase the chromecasts?
Hey there robinBath,
Here is what Chromecast Support told the OP in that thread you linked regarding MAC addresses and the Chromecast with Google TV (HD):
"Thanks for reaching out to the Google Nest Customer Care Team. I'm sorry for the hassle that this has caused you but let me guide you with the best approach in getting the MAC Address for your Chromecast with Google TV (HD). Unlike its predecessors (older versions) that can be found in Google Home App, the MAC Address is found within settings once it's fully set up. So the best thing to do then is set it up via Mobile Hotspot. I suggest you try to set it up without using the Google Home App. When the TV prompts you to scan the QR code using the Google Home App, choose the option to "Continue with the remote" and proceed from there with the setup. Once completed, navigate in the Google TV Settings > System > About > Status > MAC address. Once you have the information you need, disconnect from the Mobile Hotspot via Settings > Network and Internet > Wi-Fi and connect to the desired WiFi network as soon as you get the MAC Address concern settled."
I hope that helps you out. Let me know if you have any more questions.