Help converting picture books to PDF

[saq]

Backstory - teacher at a school. We have presentation boards in classrooms. I can (and do sometimes) scan books in to PDFs and display them for read-alouds, but this takes time and I always notice the pages being not straight and the gutter. Students don't seem to, but I do.
We also don't have any .azw3 or .kfx readers available. I can open PDF or supposedly epub.

I have some ebook .azw3 forms of a couple of the books that I would love to convert. DRM is stripped but I still can't get it to go for some of the books. Kindleunpack works great for the books that are fixed format scans one image per page, but other books are more dynamic with text and images. Converting in Calibre gives me image-only pages or pages with black boxes depending on the software (ADE, Koodo, iBooks, Okular). I can load the .epub file I get from KindleUnpack in Atril reader (Linux - it ships with MATE) and it displays perfectly - but Atril won't print as the command is greyed out). Foliate reader (Linux) will load and display the .azw3 perfectly, but when I print even though "all pages" selected it will only give me one page. Sigil displays the KindleUnpack .epub correctly, but even when I save it I still get the blank/black pages in the other .epub readers.
Anyone have some tips for a method that would work or do I go back to scanning paper copies?

[saq]

Can't edit to add, so here is an addendum:

This is what the converted books look like in most readers:

https://drive.google.com/file/d/17CD...usp=drive_link

https://drive.google.com/file/d/1j94...usp=drive_link

Folate (and Atril) render it properly (.azw3 for Folate, the KindleExtract .epub for Atril) but will print only one page or nothing respectively:
https://drive.google.com/file/d/1v_L...usp=drive_link