Here's my update for the Twilight Pack. I've only seen two animals from the pack IRL, the red fox and the common wombat, and of those two I've only seen the fox in the wild while I've seen the wombat in both the wild and captivity. Red foxes appear to be surprisingly rare in Australian zoos given the abundance of the wild invasive population, but I guess most people wouldn't be interested in seeing the animal that slaughters all the possums and bandicoots in their backyard in a zoo.
I've also changed up the structure of my tierlist a bit this time to include some additional categories. Now I've also listed distinct species for which I've seen a virtually identical relative IRL (Sumatran orangutan, Aruba Island rattlesnake and domestic water buffalo in this case), and I've divided the animals I haven't seen by whether or not they are kept in Australia. There's actually only a small number of PZ species present in Australian collections that I haven't seen yet.
EDIT: Forgot to mention I'm now also including the species I saw at Sea World (distinct from the American franchise) when I visited it as a kid, which adds polar bear and California sea lion to my list