Try working at retail when people come running up to you like zombies when you're clearly busy and demanding that you show them where the _____ is when it's right next to them. (ノಠ益ಠ)ノ彡┻━┻
From what I can observe here and from her other playthroughs as well I think her fear is genuine, shes a scaredy dog and easily panicked but since this game in particular isn't that scary I think she just recovers a lot quicker which might give the impression that shes faking. The CCTV jumpscare scene is one example; it's loud and sudden which made her jump but the monster itself isn't scary and was why she said "that wasn't so scary after all" and recovered quick.
