I don't understand what's wrong with considering the novels canon. As far as I know they don't contradict the manga. If something happens in Boruto scans that obviously contradicts the novels (Kakashi falling in love?), then definitely it would invalidate novels, but I mean, something had to happen between Chapter 699 and 700, and Itachi had to have killed his lover somehow, etc.
It's not the same thing as the anime where if certain events happened in between manga events, then the manga chronology makes zero sense (Kakashi vs. Sage Kabuto; Chunin Exams 2, etc).
In debates and stuff it's better to keep it manga-specific because it's easier to work with manga scans than text, but