Diddy had his close associates sign an iron-clad non-disclosure agreement that prohibited them — or their heirs — from speaking publicly about him. The explosive three-page NDA prohibits workers from talking about him, his family, or business associates and remains in effect “for the life of [Diddy] plus 20 years or seventy years, whichever is longer,” the document obtained by RadarOnline.com said. “The [NDA] shall inure to the benefit of and the be binding upon the parties hereto and their respective heirs, executors, administrators, representatives…designees, successors and assigns,” the doc…