I would trade #3 for Jokic in a heartbeat and I think the Nuggets would laugh us out of the room. He is a stud
Jokic and Nurkic are very different players, though. I'm fine with Jokic, and I think you're right that the Nuggets would never consider trading him. But Nurkic hasn't shown nearly as much in two years as Jokic has shown in one.
Nevertheless, Nurkic has been impressive - and, not incidentally, he's been especially impressive as a rim protector; that's exactly what Ainge says they're looking for.
Kudos to the Nuggets for their foreign scouting.
Knee injuries are always concerning, especially in such a large man - although it was not a ligament tear. All that weight coming down through the joint amplifies the risk of a chronic problem.
Is he available? The question turns on: can you play him with Jokic, and is he a long-term starter. I'm coming down on no for the first question and yes for the second. So, I think he's available.