Re: Need some Guidance...Concert type shoot coming up.

If there is track playback, id concentrate on getting good mixed ambience from his board by means of a sub group, and syncing up the playback files later.
To a degree you have to decide if you trust this guy to
1) get it right
2) Understand your needs and put them high enough up the pick list

If not then youve got a much bigger sound job to do and id be looking to record all key "live" elements as direct feed (ie not affected by his faders) such as live mics and audience

Nb Dont be tempted to try to run your inputs too hot. Theres little to be gained by risking distortion. a live auditorium mix is very forgiving with natural verb etc, but a recording clipped is awful. keep inputs a little cool so theres space for the peaks to go into, and smooth in post

Peter

Peter