Why Are Talking Heads Not Discussing...
... the fact that Presidential pardons apply only to crimes under federal law.?
So, were Mueller's investigation to uncover crimes committed in states where businessman Trump has done deals, say NY, NJ or FL for starters, and the attorneys general of those states, or other jurisdictions within those states obtained the evidence and secured indictments: pardon, shmardon as they say.
This is the real danger of Cohen flipping, IMO.