Really? I thought the ambassador animal building was open to the public. Although it's been a while since I've been, so I'm not sure.Only 5 places have the dwarf croc species (others may possibly, but don't label at species level). Polar bears and okapi aren't necessarily rare, but their numbers are dwindling in the US.
Behind the scenes as an ambassador animal, and it costs several hundred $ for an adult to see the ambassadors.