Re: RAW evaluations and graded versions
My guess is that Geoff has his hands full and may not be interested in mucking about with installing ffmpeg and figuring out the proper set of command-line arguments to get it to output Prores 4444 xq, and I don't know if ffmpeg fits within his workflow. But it is worth noting that ffmpeg is free, open-source, runs on Windows, and can encode Prores. I have used it for this purpose to encode both Prores LT and Prores 422 on Windows.
According to the ticket in ffmpeg's bug tracker that was used to track the addition of Prores 4444XQ encoding to ffmpeg, the syntax for such encoding was to be:
It appears that ffmpeg added support for Prores 4444XQ encoding back in late June 2017.