Nobody in their right mind is going to believe what they say was talked about.
I'd believe it, but not because I'm a naïf. The purpose of this meeting may have been for Clinton to intimidate Lynch, and perhaps all that it would take for him to do that would for him to semi-ambush her by arranging a meeting she didn't know about (until the last minute), then make sure the meeting was leaked to the press. Clinton meets with her, glad-hands her, then goes on his merry way. Then, the story appears in the press. LYNCH is the one whose job it is to avoid the appearance of impropriety, so she's the one who really looks bad.
(I'm not saying Lynch and Clinton didn't discuss the investigations, just that it doesn't matter even if they in fact didn't. They never should have met at all.)