Just have them use the standard 1280 x 720 HD Uncompressed setting and render to that. Or they can simply create the entire 1280 x 720 comp, then squish it so 960 wide anamporphic and render it that way so it will match the frame size of the rest of the DVCPro HD timeline. FCP can then stretch it back to 1280.
When it comes into FCP, the FCP user will have to re-render the animation, but this does work fine. At one time Panasonic had the DVCPro HD components on their website for the Mac to download. It was in the Support page of the 1200A deck. You can also have the FCP user pull the codec out of their Quicktime folder for other Mac users.
Walter Biscardi, Jr.
https://www.biscardicreative.com
Director, “The Rough Cut”
https://www.theroughcutmovie.com
Now Posting “Good Eats” in HD for the Food Network
“I reject your reality and substitute my own!” – Adam Savage, Mythbusters