First of all, if Hillary and Trump had a conversation one day, who would know or be able to prove it? Second of all, you need an overt act. Talk isn't enough.
I'm not aware of anything like that occurring although there have been plenty of dirty tricks. Thomas Jefferson, vice-president at the time, paid pamphleteers to write scurrilous reports that John Adams, the then President, was in negotiations to take America into war. He got hoist with his own petard when the man he hired, who didn't get the position he wanted, proceeded to publicize that Jefferson held a part black woman in concubinage and had fathered lots of his own slaves. Even the Lincoln-Douglas contest for the Republican nomination got nasty. Lincoln's supporters called Douglas "The Little Giant", proclaiming that he was five foot nothing tall and about as wide. Douglas supporters and the supporters of the Democrat candidates retaliated by saying Lincoln looked like a freakishly tall skeleton, a bundle of bony arms and legs, and was the ugliest man alive, or that he looked like an ape. Perhaps it's partly because of my admiration, even love for Lincoln, but I don't know how anyone could look at him and not see the compassion, the understanding, the humanity of the man, as well as the intelligence and wit. A man like that draws you in no matter the cast of his features or his skinniness.
Anyway, I tend not to believe in conspiracy theories. I think Donald's ego got him into this, and I wouldn't be surprised if on some level he doesn't regret it. As he said recently, "Do I really need this"?
When you go to the extent of trying to steal the other sides' campaign secrets, as Nixon operatives did, then you can be prosecuted.