I wonder why they switched it from unlisted to private. I mean, the event was originally going to be held on the Muppet Guys Talking site, only for site traffic to cause issues. But even when it was to be part of the site, it was to be free as long as fans registered (and registration didn't cost anything), and I thought the e-mail said that the video would be available to watch after the live stream.
I just had a thought that maybe those who registered would get a password or whatever to view the private video, but I think there's a 25-user maximum that can sign in to private videos, and I'm sure a lot more fans signed up for this.