I have managed to get Cho’Gall, Twilight Chieftan into approximately 4-5 of my my Dungeon Run (either Tombs of Terror or Dalaran Heist. I suspect you could get him in the Kobolds and Catacombs Dungeon run too via the Amulet of Domination but it would be crazy difficult.)
decks via Bob’s Tavern(so it is in the deck prior to the start of the game.) After about 15ish games, he has never once triggered an anomaly. I typically play with the Twist on. I dunno if that makes a difference. I assume I could just be having flipping Tails every single time but that seems unlikely.
I know ya’ll probably have bigger fish to fry but I thought I’d report anyways.
If you could pass onto whomever manages the product roadmap, I’d pay on a fairly regular basis for new Dungeon run packs/bosses/classes/buckets. If enough of us say something, it might be something that they could make on an Annual-ish basis.