Hopefully it wasn't pulled due to someone posting about it in public since it's not on the list or lyngat.
? Unless you're talking about something different than what I think, this has been listed in Lyngsat for years, although not under the most descriptive of titles.
This mux has gone away for a while in the past. Once it came up on SBS6 for a while, so you might check there.
However, one thing about this mux is that the various channels haven't always had the same content. Usually, there has been either MSNBC or CNBC or both, and sometimes regular NBC programming, but it has changed from time to time, and I have been under the impression that this is mainly used for live uplinks of newsfeeds and such, and that they just put the above content on when they're not using it for live transfers. Maybe this is just in a period when they don't have any particular reason to put things on there. I seem to remember years ago, one of the Atlantic sats had a mux where they would pop up HBO or some similar movie channel when they weren't using it for feeds, and actually I've seen posts from people who said that they saw HBO on this NBC mux occasionally, so I think the only reason we've been seeing content is that some uplinker just put on some programming as filler.
EDIT: While typing the above, one of the 4 channels popped up with an NBC soap.