I don’t think he knew. If he did, he would have told the reporter that he knew.
He also didn’t turn away, or blink, or do anything to make you think he was lying.
Plus, no way he could hide this. People on the plane probably didn’t know either.
He may have known she was dying, but I don’t think he knew she had died.
He may have known or not, or she may have passed some time ago and they just announced it—who knows with the Deep State!