Yeah, we can't assume material from older games is canon, but that doesn't mean it has to be different in Dangerous either. There definitely aren't 8 galaxies or cat people in Dangerous canon for example, whatever 1984 says. But Veliaze is still referenced, even if it maybe didn't involve thirty motherships like FFE says. The general overarching themes seem to be the same, if not the specifics. Anything of specific importance to Dangerous should be referenced in some way by Dangerous anyway, you'd hope.
I would still include the Elite Dangerous novels, because they explicitly were canon at the time of release and I don't see any reason for that to have changed, but that's a different debate. I think there's a good chance the conversation you're referencing didn't differentiate between the Dangerous novels and the novels for previous games like 1984 and FFE.