I think the key thing is what Chie says at the end, maybe what Rise says in response. Going off the game, at the start Rise says "Now then, let's all do our best deadman's float" or something like that, then when she pops up again I think she's saying something like "Why aren't you joining in?" Then she says "What's wrong?" but after that I have no idea.
I remember the scene in the game well. There, Rise does ask everyone to watch her do the deadman float. But in the game, she had a towel over her at the time.
In reference to the note about Chie's dialogue in the last panel, I think it does make sense. I feel like I'm stating the obvious here but since it does say "Both [meanings] make no sense" in the commentary of the translation...
"No hair" means pubic hair and because Rise just lay back and opened her legs, they could all see that she was shaven. Because it's apparently a pun on "no injury", it can be used in as innuendo like that - though it's not as if what Rise did was particularly risky or anything, though even in the game it was presented as a pretty outlandish and quirky thing to do.
This may well go down as the worst joke in history, but I was trying to think of a way to "normalize" the joke into English as it seems to be one of the least translatable examples I've ever seen. But I was thinking something along the lines of "Well, I'm just glad you weren't actually in a hairy situation..."
What about something along the lines of "That was pretty bald, er, bold of you!"? That's probably how that gag would go in English, I'd say. US comedy especially tends to use the "Freudian slip" rather than double entendres.
Is it just me or was Chie's last dialogue removed?
And for my next trick...Playing dead!Huh? What's wrong?Ah!Wow! Amazing!How was it? How was it?W, where are you looking?!We, well, even though you died, good thing you didn't have any hair, or rather..