Quick and Easy Questions (please read the OP)

[Viola]

Can you use the moves of Primes who have left the site?

Your characters can only use moves they own.

And, since they've left I doubt you'd be able to mimic them.

That said, if you can track down the approval link of their move, you could buy it yourself (but change their name to Warren/Raf).

But... that's unlikely to fit your character. And a lot of old moves might not be approved now (due to lack of details). It's better to copy their move, make it fit your character, and then resubmit it to approval. Then you can get it approved, buy it, and use it.