Sora felt the atmosphere was a bit awkward at this point. Well, he'd offer his pleasantries first. "Indeed, a pleasure to make your acquaintance. Congratulations on your engagement."
Usually people understood that the information that was offered was all they were getting, and didn't ask more questions. Was she really wanting to inquire about them, or just Riku? Sora wondered if he should discourage it. "A question politely asked never hurt anyone," Sora told her. "And I hope that you would understand it is a choice to politely decline to answer." So they didn't mean to be rude if they decided not to answer, but they certainly didn't have to.