I had the same issue, and so it begs the question as to whether the exhibit is in fact too naturalistic. It is a fine line, as while us zoo nerds love to see such habitats in zoos if we cannot ever actually view the animals then one could argue that the enclosure is at least on one level a failure.
Yes, they have to be visible at some point as I saw gorgeous photos of them in the zoo's cafeteria. However, I think it was during the winter so perhaps like team tapir, they are only visible when the foliage is not so thick.
