Oh wow, I always gave the crystal to Khloe, so I never saw this happen, but damn it definitely opens my mind on this game's concept of time travel. From what you guys are saying, it seemed like time itself was in fact fixed, when her name didnt change, but then you learn her middle name might have changed, but due to MC not being sure himself, we still don't actually know if its a fixed timeline or not.
The only way we'll know (as far as I can tell) if time is in fact fixed or not, will be episode 5, if Jenny is in fact alive after MC begs her not to work there a second time. If she's still dead then damn, that's disheartening

tho considering she followed MC to the forest at the end of episode 4 iirc, she might just use the portal herself and essentially exist outside the current timeline (or she and MC's father are still alive after the "accident" and thats when they go through the portal, hence the theory of Jackie and Masked Man being aged Jenny and MC's dad)
Episode 5 could not get here any sooner lol