I hope he loses and doesn't make a big fuss over it to show how he's grown as a person, but I figure instead he'll just lose and it'll be a catalyst for him to try to pull some bullshit during the visit.
I already liked how well the boy adapted to the whole situation:
MC: "So... do you resent me for taking the academy away from you and sending you to the military?"
Brother: "Actually it fits me so well it's almost unnerving; hell, if anything I'm having such a good time I almost feel like thanking you..."
MC: "Oh, well now that's good to hea-"
Brother: "BUT THIS IS THIS AND THAT IS THAT! COME ON BOY, WE'VE GOT A GRUDGE TO SETTLE!!"