Scenario: I'm doing a 5-cam shoot for a stage performance that includes a pit orchestra, singing, dancing, acting. Actors will have body packs -- I'm not sure about a house mic or pit mic for the orchestra. My plan was to record board out into one of my PD170 channels, and record house audio on the other channel + 4 other cams.

Question: An audio engineer who's done prior shows with me was not hired for this one. He would like to take multiple feeds from the board (body packs, orchestra [which he'd mic], house), record them on his hard drive, then re-mix after the show giving me a CD. He's done a decent job scaring me into believing that without his assistance the audio will be lousy, and that anything which goes wrong [e.g. they forget to bring up someone's body pack, so house audio would be better to insert] could be corrected by him to create a better production. Without him in this scenario, if there was a drop in the board feed, I would obviously bring up one (or more) of the camera mic's to compensate (they are "house" sound).

Would you pay extra out of the project budget to bring in the audio engineer in this scenario, or have you had good experiences using just camera mic's + board?