Yes, I think they are just messing around. In reality, they are the ones behind the NNV.
This NNV will be about removing Imaris from the loop. I'm only playing for the second time, essentially, but I remember how it's done from the last time. And even if Hos often "plays the Joker," that doesn't mean he isn't using it now as a cover. And Vegtam was playing along with him, and now he's going into the NNV.
