Britney Spears' Ex-Nanny -- Jamie Spears NEVER Attacked Sam Lutfi

Jamie Spears never laid a finger on Sam Lutfi's solar plex, despite Lutfi's testimony that Britney's daddy punched him in the chest and threatened to kill him -- so says Britney's ex-nanny Leah Frand.Frand tells us Lutfi's claims are utter BS.Frand…