For our skeletal friend, I think the real-world reason is either not putting a lot of thought into it or simply choosing style over realism. In-universe, one could think of it as a locked-room mystery.
234 - 241
I don’t have much to say for these pages, but there is some organic world building here, and this is where we really start to see Sigrun mentoring Emil.
242 - 249
On page 242, Sigrun sees skeletons and then has that expression (on panel 4). I think she is either processing or pushing down her emotions about them.
Also on page 242, Emil panicked, and Sigrun tried to calm him down by talking. When that does not work, she slaps him. On the next page, Sigrun goes back to trying to reason with Emil. I don’t like the trope of hitting someone to calm them down, and while I think it can work in real life, I would not recommend it, no matter how dangerous the situation. All because something can work, does not mean it will and it could make the situation worse.
Taking it for what it is here though, I think Sigrun handled it fine. It was a dangerous situation. She tried talking first and then, after calming him down, talked to him again.
Lastly for this page, Lalli’s expression on the seventh panel (third to last). I just really like it.
For page 243, I’m just noting Sigrun's comment on the dead being, “kinda said.”
Page 245, I love the tone shift. From the excitement of Sigrun and Emil to Lalli’s quite caution. And how this page is framed, it gives the reader a sense that something is going to threaten them soon.
Page 246, to be fair to Sigrun and Emil, I don’t think most people could just go out and grab books that have high-value to collectors. What art, science, and history has been lost? How much do Danish collectors care about old information in their own language if they can find it in others' and translate it? What “low art” will people pay big money for?