First, apologies for taking forever to answer you! I hope you were able to complete the course and that you continued to enjoy it! I just visited last weekend the LIW sites at De Smet, Walnut Grove, and Burr Oak, IA.
I’m not a huge fan of Fraser’s Prairie Fires. She made accusations against Rose that simply had no basis in fact and she barely disguised her contempt for Rose. I don’t think she like Laura all that much either. This lack of objectivity makes me question much of the book. Fraser is completely wrong about farming in South Dakota, too. The best review of Prairie Fires is by John E. Miller in Midwestern Review, Spring 2020. I’ve heard from Wilder scholars that Fraser treated them and especially the folks who run the LIW home sites very poorly. So I’m not a big fan. That isn’t to say that there isn’t anything of value in the book, though.