Who is the instigator, Andy? Whose action did Putin encourage?...

Who is the instigator, Andy? Whose action did Putin encourage? Read it. 'Someone else's actions.' He can't be an instigator and the participant Andy, contrary to your post.

while instigate implies responsibility for initiating or encouraging someone else's action, and usually suggests dubious or underhanded intent ("he was charged with instigating a conspiracy").