I am not sure why you addressed me for your question but I only try to answer from my memory. Please forgive me for any clumsy mistake and save me from embarrassing myself. 
As memory telling me, at that time Ven. Sujato was in the middle of going through the whole vocabulary at the end of lesson 8 to reinforce the pronunciation and giving some interesting details of each word along the way. When he addressed the word viññaṇaṁ in the vocabulary list, I think he linked to certain notion around this word because there is at least a thread in the forum such as this one:
which people were trying to spin up other meaning/interpretation of this word. So, Ven. Sujato was preferring to focus instead on the context and this word got the meaning similar to vijānāti and pajānāti which are all pointing to the meaning “to know”. This part I only remember vaguely: He also mentioned something like pajānāti also pointing to as knowing completely while vijānāti is something like just merely aware of.
Ah it has been a few days so that’s what I can recall, again my apology for my futile attempt. 
I don’t know how to re-watch the zoom record, anyone knows how please kindly tell?
Or even better, you can ask Ven. Sujato himself to repeat for 100% certainty.