Thanks again guys. Apologies to John for our spat. I use a 442 mixer. The reason i did not mention it in my original post is that my plan was to send 1 track of audio to the Zoom through the mixer, and the timecode from the camera directly to ch 2 on the zoom, not through my mixer. I thought if I just padded that signal, I would avoid potential problems, but perhaps I am creating un-necessary ones with that plan.
John is correct about the digital file only to be used for a transcription, so quality is not the primary concern on that file. The camera's audio will be used in the edit. The transcription house can read the timecode and add that as notes to the printed document so a rough "paper edit" can be prepared.
I understand the networks and news magazines do this all the time, so my original post did not include all the details. I thought the Zoom H4 was popular enough that someone would have gone through this and tell me how they dealt with it.