Not knowing all the details and logistics with this location and client all I can do is say what we would/do do:
Wireless Lav on the speaker, If there are 2 presenters, 2 wireless mics. If they change speakers, hand over the mics.
Clean audio into your camera.
With slides, you ride the iris. You expose for the speaker, follow them around, when they refer to the slide, pan over, iris down.
Repeat.
Chris Tompkins
Video Atlanta LLC