Do you really believe Trump is that naive? Maybe when he first got into office he was overly trusting of the powers that be. But he's a fast learner and the bloom is definitely off the rose.
It’s not a matter of naivete. Rather, President Trump believes very strongly in his own powers of persuasion. And why shouldn’t he since his entire life’s experience reinforces his confidence. But the whole Mueller thing is about setting him up for impeachment, and I don’t think the President fully appreciates the danger. He is not naive or ignorant, just naturally inclined. The very fact that his attorneys are negotiating with Mueller indicates so.