Formatting skeleton notes

I’m compiling a textbook in Malala theme.
My co-editor developed skeletal outline notes (with underlined “blanks” to guide student note-taking), but they won’t format correctly (and will be a nightmare to do so by hand), since they contain so many underlined blanks.
My first thought was to upload a PDF, but that file type isn’t supported by PressBooks. My co-editor thought we could just include an Appendix with links to the skeleton notes in for each chapter, in Google Docs. This solves the formatting problem but doesn’t make the skeleton notes viewable in the PressBook.
How would you recommend that we share the skeleton notes, to maintain formatting and maximize accessibility?