Is William Shatner joking when he says that he disputed with an astrophysicist about black holes?

1)If he did say that is it funny? Is it like a butcher disputing with surgeons? I don’t have an audio/video where he says that,

2) Why are the actors mentioned in the same sentence with ? In the film, Shatner, 85, interviews celebrities, scientists and “thought-leaders,” including Canadian astronaut Chris Hadfield, science broadcaster David Suzuki, actors Whoopi Goldberg, Jason Alexander and Ben Stiller, astrophysicist Neil deGrasse Tyson and theoretical physicist Michio Kaku.”
https://www.thestar.com/entertainment/television/2017/03/13/shatner-goes-back-to-the-stars-in-tv-documentary.html