Episode 81: Rumors, Bargains & Lies/Moments of Transition (Season 4, Episodes 13 and 14)
Synopsis: In which the Minbari Civil War comes to a head and the new Grey Council is revealed.
Space Command Redemption: https://www.kickstarter.com/projects/58936338/space-command-redemption
The Minbari capital city is named Yedor. I’m not sure if it was named on screen at any point.
Operation Downfall was the proposed land invasion of Japan: https://en.wikipedia.org/wiki/Operation_Downfall
Jon was close though - Olympic was part of Downfall, the invasion of southern Japan.