NPCs can be nigh-omniscient, acting as sages or repositories of arcane knowledge or whatever else the GM deems appropriate to give to the players at any point. Having PCs act this way is... a bit odd in most games. But as we've seen many times, this isn't most games.
[Reminder: Our guest commentators have not seen Rogue One. Part of the fun is seeing how their untainted impressions re-interpret the movie through the lens of our comic.]
Will Jim be able to handle two characters who are so different? Will he experience a psychological break due to the strain? Will the characters have to engage in some sort of gladiatorial battle for control over Jim's psyche?
That would be fun, but probably not, Jim is already a master at compartmentalising his intelligence so that it's only applied to science. It shouldn't be a stretch for him to apply this kind of mind division wizardry to roleplaying.
Jar Jar: So youssa planet youssa lookin' for must be summawhere near Kamino!
Cassian: But, we didn't tell you what we're looking for.
Jar Jar: Mesa know. Bye bye now!
Chirrut: He's a genius.
Mon Mothma: That's seriously tripendicular! We can, like, totally scan systems near Kamino. You can check out that Polis Massa place in the meantime, fer shure.
Bail Organa: Sounds good to me!
Bria: Sounds awful to me!
Cassian: Jim, that's really good roleplaying. Two characters with different motivations.
Chirrut: Wow. Jim's split the party before, but he's never split himself.