If you are clear about your brand promise, set forth messaging guidelines and implement training and policies, then trustyourteam to engage on behalf of the brand.
I've been in that situation many times and you trustyourteam - you trust the integrity and safety of the car, so why would you not trust them when they give you a guideline on what to say?
This will not only prove to yourteam that you trust and believe in them, but will also free up your time to focus on the higher level tasks, that should not be delegated.