How can you prove, beyond your own speculation, that someone is having an affair? Don't you have to be in the motel room with them to see them actually having sex? I can't imagine but that I'd be extremely reluctant to report that someone was having an affair, because all I could say is that "it looked like it", not that it is a fact. And you could be made a fool of.
so I was trying to address those specific points:
1. How one can prove an affair beyond mere speculation;
2. It's still valid to expose a workplace affair, if one has sufficient proof.
If you're trying to make a different point, I apologize, cuz I'm a little confused here.