Just picking up something I missed
I still think there's a very good argument that Fan should get Loom Snarling Detection + Eldritch Secrets Mastery and Thalassa should get Hide the Evidence, Clark Kenting, and Masquerade, and they should both try to fade into the background while the Emperor is around, and try to avoid meeting him.
The Emperor is probably in a hurry, so if Lorgar goes out to intercept him, and we stay at home, then we may be able to make it look like Lorgar is simply modest and shares credit for his achievements with people around him, the better to motivate his followers.
I think the horse is not just out of the barn, it's broken the door on the way out and sired a whole host of foals.
Maybe we could have pulled that off before Kairos. Now the Emperor will damn well be paying attention. All he would have to do is read a transcript of that speech last turn and he will see Lorgar claim that he and Fan made Thalassa a demigod. There's no way that claim isn't worth a look no matter how busy he is.