The BBC is being scourged for having been — 25 years ago — once insufficiently open and honest with its rightful liege lords (in this case, the then Princess of Wales). Apparently they tried to trick her into giving an interview, though the BBC says it has a handwritten note from her saying she didn’t mind, and she would have done the interview anyway.
In the course of discussing this Diana’s brother is quoted saying “he ‘draws a line’ between the [BBC] interview and her death two years later.” It’s an interesting phrase, of a rare sort that I call auto-antonyms. The same words might mean two diametrically opposite things. I think he means to say that the two events are causally connected — as though by a straight line. But he could also mean that even though one event followed the other, he considers them to be completely separate — to emphasise which he would draw a (dividing) line between them.