Simon I think the point of this would be if he is filming in front of a green screen, then it shows he is not above deceiving people. Let's look at the record. First it was taking a break for mental health. In reality, he took off without his family during the holidays to spend time in Thailand, "scuba diving and enjoying the food." Next it was, "Watchtower caused me to cheat on my wife by screwing up my sexuality." Then we get to see what his "team of lawyers and his PR firm" did for him. Now we might be looking at him filming a green screen version of "the bunker." This speaks to his continued deception and that is what makes it a real issue.
Granted, if filming was his only deception, then this would be nothing. This is merely additional proof that the guy takes us for idiots.