An example would be if you decide to corrupt Iris with his dad, Arthur. During sex, he tells Ashley how he slowly made Iris "open up" with him and how they are now fucking without constraints. And the scene didn't feel out of place because it connects with the current event of the game.
That's the thing, it's not a random shift in perspective because the change of perspective ties well with the narrative just like my example of "thinking about the individual" or Arthur narrating how he corrupted Iris.
That is different from what you expressed previously. It's still Ashley's perspective, hearing Arthur recount the story. If pics/vid were used, it would also be from Ashley's imagination. Story still told by her POV.
Yes. That could be possible if done right in ORS. But at this point, it would, just like your Ashley example, have to be done through a story recounted to Ian or Lena by another character, where their imagination might take the place of pics or video.
An invisible narrator dropping in from out of nowhere 1/3 of the way through the game for tea and a quick dirty story just wouldn't work, unless done with utmost skill and well-considered intent that is conceptually meant to improve the story as a whole. That usually takes "threading a camel through the eye of a needle" level writing skill and often a whole lot of pre-planning before even sitting down to write chapter 1. Eva's a good erotic-game creator, but that's a tall task for any writer. I just don't see it happening unless she breaks into a windfall inheritance and commissions Charlie Kaufman because WatsonJohn wants some good narrator-told jack-off material for the rest of the ORS run.
Edit for clarity: Eva could also bring in a narrator at this point if she were a crappier writer who didn't care about quality. Since thankfully I don't think that's the case, the closest you're going to get outside of shared pics/vid is of Ian or Lena hearing a story from another character and imagining the actions as they're told.