What is really cool about the Skyfari ride is that a visitor can see all sorts of habitats that normally are behind fences or impossible to view from the main pathways. I think that there must be a lot of hoofstock behind the scenes.
If those pens are in the old goat & sheep turnaround (in the valley behind Polar Bear Plunge), they hold several hoofstock species moved for the Elephant Odyssey construction.
While I also saw a lot of hoofstock in these exhibits when I went on the skyfari ride, I am almost certain that I saw a kangaroo or wallaby in one of these exhibits.