In my estimation (for whatever that's worth), the Cowboys are lowballing Bryant as well as publicly denying rumors of a tape that no one can find -- in the process they're making sure everyone knows about it -- so his value around the league doesn't approximate his proper worth on the field, and more or less coercing him to actually play out his franchised year because of a damaged reputation: it's not exactly a secret that he's got some "red flags" around his character, which is totally stupid but also totally true.
The Cowboys want to franchise him or pay him a pittiance, they want him to actually play next season instead of sitting out, and they don't want another team sweeping in with a massive offer.
You'll notice that exactly none of that has any bearing on whether or not the tape actually exists, or what's on the tape, or anything to do with Dez Bryant as a human being. This is, imo, how the Cowboys are most likely to operate.