I haven't played this game so I don't have a stake in this debate, but might she not at least have told Cloud and Co during her travels with them, once she learnt to trust them? Might she not have confided in Cloud or Tifa that she'd been travelling with a friend who was brutally killed by some wierd Shinra operatives from underground? Wierder even than the Turks; some gimp in bondage gear! Yuffie has a flair for the dramatic and loves telling stories about herself. And wouldn't Cloud, Tifa and Barret put that together with their own experiences in Shinra's secret underground lab?
But again, what is specifically actionable about that? What
call to action beyond what they are already doing would it create for them?
Even assuming she felt like sharing more specifics about her friend's death than "We broke into Scarlet's basement and she sicced her pet freaks on us. He didn't make it," what impetus does her story offer to Cloud and the others that they should make a point of heading back there as soon as Sephiroth is dealt with? Especially once Diamond Weapon and then Meteor wreck the Shin-Ra headquarters, and eventual reconnaissance of the area (after all of the immediate infrastructure and medical needs have been addressed) yields no further survivors or bodies?
Most likely, if she did bring it up, they'd be more concerned with offering their condolences about her friend than making bestiary inquiries. And even if they did compare their editions of Encyclopedia Midgaranica, Barret's just going to be like, "I damn sure bet Scarlet keeps some freaky stuff in the basement. You wouldn't believe the shit we ran into in Hojo's zoo on the top floors."
For that matter -- and this is a question for
@Clement Rage most of all -- why does Yuffie randomly decide that her former Shin-Ra executive friend, Reeve, definitely doesn't know about the security goons in the glowy suits she ran into or their Lovecraftian bondage buddy? Why does she feel the need to tell him about this when he doesn't ask her specifically if she suspects there's a secret army in an enormous secret underground facility headed up by a secret cadre of extra special supersoldiers?
And for
that matter, seeing as Reeve at least knew that Shin-Ra had a program called "Deepground" -- the details of which he was told was on a need-to-know basis -- why didn't he investigate the matter? Unless he didn't believe there was anything left to investigate after the world, Midgar in particular, got wrecked? Or maybe he did, yet there was nothing to find?
There are soooo maaaany reasons why the specific series of discussions that would need to happen for anyone to make enough of Yuffie's encounter with Deepground so as to prevent the events of Dirge are
preposterously unlikely. Even with discussions happening, the specifics of what Deepground actually is are so outside the boundaries of what could have been reasonably expected as to make the notion a slums-to-plate reach.
You're technically right about the reporter, but I can't imagine the WRO not taking an interest in a crew poking around Shinra HQ or allowing it to happen without being involved.
Does "taking an interest" have to amount to trying to strong-arm the media at gunpoint or dictate what a group of civilian volunteers is doing? Does a former Shin-Ra executive with noble intentions really want that kind of publicity?
Though "We've been told we shouldn't be here" could explain the urgent, almost frantic pace at which the reporters and investigation crew were making their way into the ruins? But that again points to this not being the WRO conducting this investigation.
The big theory with Sephiroth is that he's from after advent children, but in this case he's not from after the movie "advent children", he is from after some slightly different version that would have happened in an unaltered remake continuity, and the whispers version of Kadaj and crew were also from that alternate version.
I do actually think he's our original Sephiroth from after the movie, and that he's simply -- to borrow some "Loki" terminology -- now become a Variant of sorts.