Concerning the latter first - I do not believe there is anyone in this 'game' who could not operate as any of the roles. It wouldn't make any sense to bring in someone who couldn't be a VIP. Whatever is being levied to ensure compliance with the actions of the VIP would be just as effective as Missile, I am sure.

As for instructions about lying, being trained to bark at a particular time isn't so impossible.

[There is a moment's hesitation as if she's about to say more, but she'll glance at Simon.]

A skilled trainer and an intelligent dog would be capable of it, I believe.