I agree that if any of the Scions were to be kicked off the stage, Krile has the highest chance.
Having said that, I don't actually think she'll be killed as such. More likely that she'll be simply written out as "doing other things elsewhere". She still has a big role in Eureka, which is a large enough piece of content that I don't think the "content is stuck in the time of their patches" can hold for very long, unlike the aforementioned Estinien DRG issue, or Zombie Nanamo in the CUL 50 quest. (Or Urianger casually hanging around the Waking Sands until you finish the ARR Extremes, at which point he casually walks away.)
On a tangent, I've been playing FFIV in preparation for Endwalker, and it reminded me once again of how the complaints of FFXIV always having character death fake-outs is somehow "cheap". FFIV is full of character death fake-outs; FFXIV has a much higher actual bodycount, while still being comparable with the number of "oh no, this character has sacrificed themselves in a way that surely they cannot survive, even if nobody has seen the body".