I like the idea that Ahsoka does know Anakin returned to the light and to being a Jedi after his death, because it makes her line of “the best of us” even more painful. She had so much trouble believing that he could possibly fall, she flat-out denies it when Maul says it’s going to happen, she spends the next 16 years in denial, Malachor really has to have done a number on her, but she probably knows he died in the light, there’s probably a part of her that is so proud of her master for coming back from the deepest parts of the dark, to come back to the light, to the Jedi!
He’s the best of us, for everything she knew of him when they were Master and Padawan, but also for being able to do something that difficult. He came back from being DARTH VADER, like, do you KNOW how hard that had to have been, that steeped in the dark side and decades of the most monstrous behavior? And he did that!!
But even someone who could overcome that much darkness to come home still fell, still was vulnerable to his feelings. Anakin is capable of the impossible, he’s the greatest Jedi she’s ever known, not in terms of steadiness, but in what he can and has done, and she has to be so happy for him, she has to believe there is so much greatness that can be accomplished in this galaxy, but that it also comes with the bitter, painful knowledge that even people who are capable of all those amazing things are also capable of all those horrific things.