Hi James, nice to meet you! Here are my thoughts.
First of all, I would say the more info you have about the values of your audience the better. What do they really want?
I could mind read that as volunteers with no mental health training, they might like to take a 7 day training that will allow them to get paid handsomely for helping people make much bigger shifts in their mental health than they are currently making. So without knowing anything else, if it were me, I would start with something like that in the “Why” section of my talk.
“Who here would like to be able to help people make MASSIVE improvement in their mental health in a matter of hours or minutes?”
“Who here would like to get paid hundreds of dollars an hour to do that? Would that be of value to you?”
I might also ask a thought-provoking question like “WHAT is Mental Health anyway?” And let it sit for a minute and let people ponder, before giving your own complex equivalence. Many people think of mental health as binary: either you’re mentally healthy or mental ill. In reality it’s a spectrum. And you could define mental health as something like being at cause/empowered, congruent, and being in positive, joyful, resourceful states most of the time.
So HOW do we achieve greater mental health? By letting go a negative emotions and limiting decisions and by integrating parts… and for that there’s NLP and TLT.
If you only have 45 minutes, then maybe just do something like having participants greet each other first like someone they really don’t like, and then like an old friend they haven’t seen in ages, and notice how different their experience is just from holding that different thought in their mind. And you mentioned talking about the NLP Model of Communication, so you can tie back into that: perception -> state -> behavior.
For any NLP demo/exercise you’ll probably need about 15 minutes which is a big chunk of your 45 min talk, but possible if you want to go that route. Personally if it were me I probably wouldn’t go that route as it would be too rushed and not much time for What If after that.
Those are my thoughts for the moment without knowing more. Good luck! Sounds like a great opportunity!