Well, if you choose for Ian to fight, he can potentially gain a will point and gain a solid dose of self-confidence. Having a fight against someone who's already part of the cast would feel too silly for me (jokes about Superstan notwithstanding). But again, i'd expect any actual differences between choosing to fight or not to only appear down the road. This is more an "issue" with updates being now shorter than full chapter.
Btw, there's a small difference if you choose to fight already -- Lena will wish Ian luck in the text she sends him before the fight /s (but the text part is currently bugged and you only get them if Ian is flat-out broke)