well, there's still a chance for teh Yuuzhan Vong to be canon, given they were concepted for the Clone Wars show. but now that this exists, that seems unlikely. or replaced, given the details of this book
we have nothing on them except for a concept art piece. so what Filoni and team had planned is unknown, if they'd even use them in the first placeYuuzhan Vong still can be canon. did not they come out from another galaxy or something ? could be threat in the future after The Grysk.