Prediction: Domino will play a role at the beginning of Part 2, helping out Cloud & team one final time and breaking the news that Wedge is dead. After this, Domino will either be executed by Shinra because of his connections with Avalanche or he will in some other fashion leave the story and not return until way later.
In the original game, Rufus Shinra's speech about controlling the people with fear isn't followed up upon until the attempted execution of Tifa and Barret in Junon. Even then it's debatable how much of an actual follow-up it is to the speech from when we first meet Rufus.
I could write half an essay about why I think it was a good choice to cut the speech from FFVIIR Part 1 and how it, in its verbatim form, is difficult to use in any scene without making Rufus Shinra look like a cartoon villain. Instead, I think that the qualities of this speech will be translated through Rufus Shinra's actions and strategies.
Rufus Shinra isn't wasteful, unlike his father. The time of sabotaging reactors and dropping plates is over. IF the game wants to follow up on fear tactics, then Rufus will promptly have Mayor Domino killed. The Turks will be competent enough to learn that Domino was helping Avalanche all this time and Rufus will not waste time letting a traitor remain alive. This will also have the effect of keeping Heidegger in line. Rufus Shinra is not afraid to have higher-ups of Shinra executed, so Heidegger better know his place. Having a higher-up executed this way will shock both Rufus's close subordinates and the people. That'd be one way to honor the omitted "fear" speech.
Problem is though... I am not confident this scenario will actually play out. Rufus Shinra, both in the OG and now in FFVIIR, feels like an enigma to me. He keeps his cards close and the game (or even his OtWtaS chapter) doesn't give me a good idea of what goes on with Rufus during disc 1 and disc 2. I feel it's 50/50 whether Rufus Shinra will have Mayor Domino executed or instead quietly monitor Domino's activities so that they may know in advance what Avalanche is planning. The former has shock value that tows people in line while the latter is a longer, strategic game.
An image is stuck now in my head though of Elena's introductory scene being her walking into Domino's office, Domino only having time to say three or four words before getting a bullet in his head. What an intro that'd be. Okay I don't actually think they'll do that but it'd be a neat display of Turks efficiency, wouldn't it? I definitely think that the game will omit much of Elena's comedic role and instead show her as a competent member of the Turks who is not to be taken lightly.
Whether Domino gets executed or not, I think it likely that he will send out help to Cloud & team at the beginning of part 2. From his point-of-view, Avalanche DID give President Shinra his "comeuppance". I doubt the former President would have given Domino access to any security cameras from the 70th floor (assuming that floor even had security cameras), so he has no idea that Sephiroth is the one who killed Shinra senior. Domino does make sense in the narrative as the person to break the news about Wedge's death though, because we already saw them interact and Domino could easily have confirmed Wedge's death over multiple security cameras. It just feels more organic than, for example, the Turks meeting Cloud & team later and confirming "That fat guy what-was-his-name-again? Oh right, he's dead."
Domino will send out either Hart or the "Collaborator" (from outside the battle simulator) to meet up with our main characters outside Kalm, a city that is currently heavily guarded by security officers. Domino will confirm the latest with Avalanche (+flower girl +lab rat dog) over video. Hart/Collaborator will then help ensure that our team gets phones and supplies for their journey. Maybe this is also how our team might get a new vehicle to help them travel from Kalm to the Chocobo Farm at a decent pace.
I stress the security forces at Kalm because in the original game Shinra's security appears overly relaxed after the highway chase in Midgar. After having spent all those resources chasing down Cloud & team, why does it suddenly stop? At the very least there should be security officers in Kalm searching for any potential Avalanche members. For this reason I also don't see our playable characters casually entering a public hotel, not unless it also includes a door to a hidden Avalanche meeting room or some such. All this makes me think that exploration of Kalm will be severely limited in FFVIIR Part 2, which will save Square on some resources in designing the area.
