I've had some experience lecturing - in philosophy, not level design unfortunately - it can definitely be nerve-wracking until you realise you're not being judged, you're being listened to! You're not expected to be 100% correct about everything, especially with such a broad topic to which there are multiple approaches. This is just my opinion but I think the students and teachers would be more interested in your personal approach and what you have learnt from experience, how you bend the rules etc. so you can always CYA like this.
Personally I would be interested in hearing about what you think makes a level fun and interesting to play and how you would approach this (points of interest, timings, etc).
Oh and time will go very fast once you're in the swing of it so you might not even get to cover everything, but if this is not the case there's always question time ![]()
Good luck!