When she was on the first call with everyone, it says she appraised both the MC and Jaye. Why would she feel the need to appraise Jaye if she knew all about her already? Because this was the first time actually meeting either of them. She then says, "Your parents spoke of you often". Since she had appraised both of them just before that, I believe her statement referred to both of them as well.
Shortly after getting off the plane, Lisa said, "I don't know a thing about you". I took that as a lie on her part. Since she's trying to figure out to whom the company's control should go, I think she's being deceitful. The MC would act differently around someone who already knows all about him than he would act around someone who doesn't. It's often easier to sneak information out of someone when they think you're less informed than you are. She might have been truthful, but I don't think so. She's the company's acting CEO: she's clever, and I think this ruse is a demonstration of her skill.
As to their closeness, I think if she already knew all about Jaye and she spoke often with both parents about her previously, I don't see how she would know nothing about the MC. He would have naturally come up on conversation from time to time, revealing things about his personality and about his different activities. I don't believe she doesn't "know a thing about" the MC. I'm not buying it for a second.