Noah has kept the secret this whole time.
Marvel Studios needs to look into hiring Trevor Noah for his own superhero movie. While actors like Tom Holland and Mark Ruffalo, Spider-Man and The Hulk, respectively, are known to spoil plot points before the movie premiers (Ruffalo especially), Noah has kept his mouth shut about appearing in Wakanda for months now. The Daily Show host has had many opportunities to reveal his role, and bask in the accomplishment, but instead, he's kept quiet. There was even one episode of the Daily Show where Noah gets excited that he doesn't need captions to understand the language that is being spoken in Black Panther (he speaks seven languages). That would have been the perfect opportunity to speak up.
A keen-eyed fan spotted Noah's name at the end of the credits and tweeted about his discovery. He proves why it's important to read the credits, which no one has done for the last three months apparently.
The character that Noah played is named Griot, who was actually the ship that Martin Freeman flew during the third act of the film. Freeman, who plays CIA agent Ross in Captain America: Civil War as well, used the ship to hunt down Killmonger's weapon shipments. Black Panther is currently available digitally and on Blu-ray.