Here's the thing: his thesis is not wrong.
When you are dealing with a pathetic, lizard-brained fool who is motivated by rewards (and he defines what rewards matter to him -- in this case, he's made one such reward quite clear), manipulating him by dangling the prospect of that reward in front of him is an elementary tactic. Fuck, if you are involved in a situation involving conflict, dangling "dude, if you pull this off, you should TOTALLY get the Peace Prize" in front of him is a fucking no-brainer.
He is incredibly manipulable. Sure, you have to be in a position where you have, or can present a path to, something he wants. I'm sure that if there was a state actor out there who had cloned Ivanka into a sex slave, they'd have a good play as well. But if you have or can help deliver something he wants (not for the greater good, or anything like that, mind you - remember, we're talking about a narcissist, so it's only about things he wants for himself), then you can fucking play him. And you'd be dumb not to.