Well, the envoy is credited by name (Korr Sella) on the TFA IMDB page and only appears in the final cut of the film for one shot during the destruction of Hosnian Prime. I remember that name showing up on the cast list very early but I didn’t connect it with anything until I read the novelization. I think you’re likely right, but her presence on the cast list since right around principle photography has me hopeful. I think you’re definitely right about the Unkar Plutt scene being included, though.