This app was mentioned in 2 comments, with an average of 3.00 upvotes
Unless it was added recently, Android TV (like the Shield or Mi Box) doesn't support WPA2 Enterprise. Actually, the ability is there but there is no UI for it. There is an app that may help, but I'm not sure if it still works with current devices: https://play.google.com/store/apps/details?id=de.stefant.connecttoradiuswifi
if you can get the APK from this or something similar and sideload it then you may have working wifi.