Can you go into more detail about your Bell Fibe TV setup? Does it only work in a browser or did you find a way to make it work with an Arris box or Android TV device (which, if it’s on the Bell network, should let you watch any channel you subscribe to)?

I’m wondering how IGMP snooping/multicast would work through the tunnel if I wanted to put a box elsewhere.

Check if your ISP has an SMTP service. I use mine for alerting when stuff breaks and haven’t had any issues. If you use your own domain name and have trouble with delivery, you could try setting up SPF.