If the guy taping had taken 15 steps backwards (putting him in the front row of the stands), this would have been legal. Also, how did they capture the "corresponding audio" from the far sidelines? Maybe it was from the black helicopter hovering overhead.
That is not correct. Any team employee is prohibited from videotaping anywhere but in the enclosed coaches' box. Even fans in the stands are not supposed to videotape.
The ESPN article originally quoted stated that the Patriots recorded audio of private conversations. Apparently you are disputing this fact with some inane reference to a black helicopter. All I can say is, I cited a source; you did not.