Anyone know when Lilly found out?

[Oddball]

And the icing on the cake is that Lilly's route is all about honesty: All choices in her route are about Hisao always telling her everything about himself without reservation, otherwise bye bye good ending.
Sometimes I wonder if Suriko was trolling us with this...

I don't see why you would think Suriko was trolling anyone with that.

I thought the message was pretty obvious.

Lilly is helping Hisao be a better person, and in the process she ends up teaching him some lessons she herself had forgotten. She wants him to be honest with himself because that's the proper thing to do, but she's gotten so focused on "proper" she lets it override who she really is and what she wants.

[Mirage_GSM]

"Always be honest to and about yourself, but be careful never to trust others to also be honest to you."

[Shockproof Jamo]

Did she actually hear the commotion behind her and Akira and find out before the flight, or was it after she and Akira had left and someone (more than likely Hanako, or even Shizune) had called Lilly to tell her? I used to feel like it's before they left, but the fact that the music box doesn't show up in his room until a couple days later while he's in the hospital kinda makes me feel like it took time for her to find out (32 hours round trip, 16 hours one way I think she says in Hanako's storyline, so there's two days minimum accounted for). Plus the fact that his parents had come back and spent time with him after he came to again and didn't mention Lilly (or that Hisao's inner monologue doesn't mention, which he absolutely would've. Plus this is Lilly so his parents would've definitely mentioned a tall, attractive, blonde woman crying over him) kinda implies to me that she wasn't there at all yet. Based on her actions when he sees her enter the room and says her name, I'm also pretty confident that if she knew when it happened at the airport, she would've been in the ambulance with him (if possible), or followed behind in a taxi (or somehow found a way to follow the ambulance) and would've been there the whole time from his admittance.

Hisao's parents are members of his immediate family, Lilly at the time wasn't (being school mates doesn't count), so she would not be allowed to even see him before he's taken out of intensive care. That's why it makes sense that it would be a couple of days, before she was able to deliver the music box. Because the hospital staff wouldn't allow non-family members to visit while Hisao's still critical.

It's pretty likely that she heard, when people suddenly started screaming that there's a guy dying over here. And correct me if I'm wrong, but don't major airports have in-house emergency first aid rooms for sudden passenger medical emergencies? If the airport employed airport medics, Akira, with a pair of still functioning eyes would've surely noticed when they rush to the scene. Therefore, once the situation became known to them, it stands to reason that the girls never boarded their flight in the first place. That couple of days delay was simply because Lilly, as a non-family member, wasn't immediately allowed to see him as per hospital rules. Pretty sure that made for a couple of sleepless nights for her...