Have you tried calling 1-800-comcast ?
Hello TanzaniteFox, and thank you for creating a post on our forum. To activate your modem you can click on this link, but if you're still having issues feel free to reach back out to me here and we can chat via private message to get the equipment up and running.
Hmmm.... Wonder if that is going to work given their particular situation ?
Hello TanzaniteFox, we haven't heard from you but please reach back out if you need assistance in the future.