I think from what I’ve read Stone is suggesting that Preibus in is the one behind the scenes stirring the pot of poop up and brought it to a boil so that Trump then had no choice but to get rid of Flynn. Preibus is a mole, serving The Establishment first, Trump second!
Preibus is Ryan’s very very best friend forever.
He may find out that he’s feeding Trump plenty of rope for himself to be hanged.