Eh....since we definitely haven't seen Jillian's heir pop yet, we have no idea if Vinnie actually is influencing it at all, so it's hard to say. But I would hazard a guess that if there is a way to influence, it would have to be more deliberate/connected. Vinnie spends much of his time with Jillian, and in FAQ City. He is also in the formal position of being envoy to FAQ.
Scroffula and Queen Post are merely allies who seem to spend no time together, living in and ruling their respective sides.
Plus, it has a little too much of a "Luke I am you father" ring to it, and I'm not sure Rob is really THAT cheesy.
I think the King is just a lil crazy and acting irrationally. Maybe he felt threatened by Racket's intelligence and feared a coup, but then once Racket was gone he realized he needed that brain so instead he turned to the next best resource, one he could make use of without it being an Heir who can threaten him.
"I'm afraid I don't understand. And also afraid that I do."
Two guys with basically the same name in a discussion about a character getting cloned.
There's gotta be a good joke in here somewhere.