Start watching at like 1:19 and see the kids don't have their own staff. Then at around 1:24 they do.
Ahhh! When he said staffs I assumed he meant people, not staves! Yeah, that's 100% CG. Here [1] you can see where the kids take a stance where it was to be edited in, and if you pause at the exact moment - it looks pretty bad, with something like a lightsaber just popping in the kid's hand.
Hmmm. Not sure what to make of this. I wish it was possible to see the raw unedited footage. It makes me question everything else.
I think you're seeing a magic trick that's been around forever: https://www.youtube.com/watch?v=o-KDuOvMAfQ&t=80s