Joey,
You will achieve the best results if you (or they) drop the DV25 files on a FCP DV timeline and use "Edit to Tape" to print it back out to DV25 tape (with contiguous timecode). You can then use those "sub-master" tapes to capture into CineWave using your normal procedure (S-Video, Component, or SDI). I realize it's a lot of work but any of the other methods you're considering will, at best, yeald questionable results.
Hopefully someone else in the pasture has a simpler idea.
Bart
P.S. Or you could just capture from the original camera master(s) with timecode/deck-control turned off.
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Bart Harrison
Multimedia Programming America
The HD Suite
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