Brief description of "In the Pale Moonlight":
The Dominion War is going badly for the Federation Alliance. A ship that has a close friend of Dax's was destroyed by a Dominion ship that traveled through Romulan territory, something that was happening more and more since the Dominion and the Romulan Star Empire signed a non-aggression treaty (something several other species have done in order to avoid war). Sisko is determined to stop this and realizes that the only way to do that is to get the Romulans to join the war on the side of the Alliance. Sisko talks to Garak to have Garak use his few remaining contacts on Cardassia Prime to provide proof that the Dominion plans to invade Romulan space. A problem happens when all of Garak's contacts get killed less than a day after talking to him. Sisko and Garak decide to fake the evidence. Sisko calls in a favor to Chancellor Gowron to have a convicted criminal pardoned rather than be executed because Garak plans to have him create a data rod (basically a future version of a flash drive) that shows a security video of Weyounn and Damar planning a invasion of Romulus. Sisko convinces a influential Romulan senator to come to DS9 after meeting with the Dominion and view the recording. After the senator examines the data rod though, he realizes that it is a fake and tells Sisko that he plans to tell the Romulan Senate. As his shuttle is leaving though it blows up. When Sisko talks to Garak, Sisko realizes that Garak planned it. Garak said that he hoped that the data rod would be to fool him, but had a back-up plan just in-case. He planned that the ship would be blown up after leaving DS9, the Romulans would find the data rod in the debris and assume that the Dominion blew up the ship to prevent the evidence of the invasion from getting back to Romulus (with Garak saying that the Romulans would think that any flaws with the data rod would be blamed on the explosion). Sisko's plan worked and the Romulans entered the war on the side of the Alliance. The entire episode was told as a log entry by Sisko, with him struggling to cope with what he did under the gist that the end justifies the means. Sisko then admits that he would still do it again, then deletes the entire log.
Hal, I am not sure which episode you are talking about as that doesn't sound like any episode I have seen. I am trying to think of some. There are a couple of episodes involving "Benny Russell". Benny was a science-fiction writer in the 1950s. All of the DS9 regulars (including the actors who played Martok, Dukat, and Damar, among others) play characters in this world, letting us see what they look like out of make-up. The only time travel episode I can recall is the two-part episodes "Past Tense (Part I)" and "Past Tense (Part II)" when Sisko, Dax, and Bashir end up in 2024 San Francisco and Sisko ends up having to replace Gabrielle Bell, a man who helped end massive riots and led to closing of the Sanctuary Disrticts (basically ghettos were mentally ill people, violent people, and homeless people, were all forced to live because the government had given up trying to help them) after people became outraged at what was happening in them and forced the government to pass real reforms. This was funny because Sisko's image replaced Bell's in history books and would be mentioned a few seasons later when Sisko got a visit from Temporal Investigations in "Trials and Tribble-ations".