You're suggesting that as fanfic, right? That would be interesting to read.
Minna was never going to do that story; at least, not after fairly early on, when she had Emil make a racist comment about Chinese and the comments section blew up on her. She said then, basically, that she just wasn't ever going to discuss non-Nordic peoples again, rather than learn how to do so.
(The comment wasn't Emil being deliberately racist; he was just being ignorant. Minna may also have just been being ignorant to start with, but she handled it IMO extremely poorly.)
But, yeah. I expect she was, originally, going to do a story about Emil and the fire. It doesn't make any sense to have had that in there otherwise. She came back first to the assorted hints about something hunting Hotakainens (I think I spelled that wrong) and Grandma's one mistake; and that, unfortunately, is as much of the characters' backstories as we're ever going to get.