[Well for starters, Kari is going to make a bit of a show of looking really confused as to why Ginia is still writing to her, but then mock comprehension and shakes her head -- there's no reason "Kari" would know Ginia is mute, after all, but still no reason she would question it -- that'd just be rude.]

Oh! No injuries, nope! I-I think an old tennis injury flared up a but when you pulled my arm, that's all.

[Says the girl who has never played a game of tennis in her life.]

But thanks for saving me! I seriously thought I'd have to start planning out my future in that stupid room.