They’re not on the sign for some reason, but there’s also Addra Gazelle and Eastern Bongo, though the Bongo are rarely put on habitat since they can interbreed with the Kudu and Sitatunga.
@Breckenridge Thanks! Based on the documentary, I had a feeling there was more unsigned. Unfortunately, because most of the path was closed off, all I saw were the rhinos, oryxes, and Thommies.