Tobirama could simply pull the rods out and the 3 could launch an attack against him and stop him from becoming the jin. Hiruzen might not be strong enough but there isnt anything Madara can do to hurt him. But as others have said its plot.
and plot is the strongest weapon on any story.
Plot is what dictates why the main cannot die, naruto still has to fight sasuke so both of them will live. Sakura is part of team 7 and has a role in this finale for team 7, she will not die.
Plot made Shikamaru grow up after Asuma died
Plot made Tsunade the hokage
Plot made Madara such an evil jackwad.
Plot is the most powerful and evil thing in the naruto universe, otherwise Kishi is saying "Dance my puppets!"
But yes, I doubt a NS moment would suddenly just come forth but consider this: the propsect of naruto losing kurama, getting his bijuu extracted is very high now. Just like when we saw Naruto seeing Obitos memories of Rin, there was a lot of potential for another connection, another relation, had naruto said how he felt about sakura to obito as he did about rin, that would have been it. Yes it didnt happen, but if it did, it would still have been in complete context with Obitos character and narutos goal and ways of just trusting others not going down the dark road obito did. So what about the current situation? Its if Naruto gets kurama yanked out, this could be some big emotional event on many characters, but the one who knows this most is Sakura, she was there and scared at the prospect of this happening to naruto, way back before any even big issues or pairing wars really even esculated, this was years before Hinatas pain moment and Sakuras hug, then 469 put the pairing war into full force. Kushinas foreshadow esculated the pairing war further, but since that foreshadow has been linked to sakura, things are pointing to NS. But on this case, if naruto is to lose Kurama next chapter, be exhausted to the point of near death, even though his uzumaki stamina would allow him to survive, the impact of seeing him in such pain, it could be a big emotional toll on Sakura. The situation is she doesnt need to worry about Sasuke, she doesnt even trust him. So what is her view on how Naruto being subjected to this, if it finally occured, how would she react? Sakuras next action may suprise many people unlike us. Is the moment granted to happen? No its more likely to just not happen, but its possible because its still in context with the current situation, hero is about to get seriously hurt in a method from the villian in a way the hero and heroine learned long ago would generally kill anyone else in the same situation. Sakura thinks naruto will die she doesnt know about the stamina aspect but its still a reason for her to be perfectly frightened for his wellbeing more than ever.