I also suspect she didn't think about the Robert situation that happened in the previous chapter when writing the scene of Lena grilling Ian because Ian never brings it up or even reflects back on it in his thoughts, which makes the Holly's path seem like a completely separate event, not influenced by the player's choices in the rest of the game (except for Ian's choice to get close with Holly or not).
That's my experience also. My first Chapter 8 playthrough was from a save where Lena had remained "faithful" to Ian throughout the story (other than some voyeuristic fantasies and girl-on-girl), but Ian had either slept with or kissed Holly. So Lena's reaction seemed plausible, if a little harsh in the regretful-kiss scenario where Ian had otherwise remained faithful. But
I just feel like Eva was probably overwhelmed and lost in the process of creating this chapter, so neglected to write at least one alternate reaction to the Ian/Holly scenario. It's a major plot-point that absolutely needs at least two scripts, even just an all purpose reflection
There are a
lot of threads to account for, so the occasional inconsistency is expected. But this is the first major one that affects at least 50% of playthroughs, so I really hope she does something to correct it for the sake of quality control before the release of Chapter 8 Final. It knocks down the quality of the game a lot for people that care about cohesive narrative.