Yup, Campy 9- and 10-speed RD's are no different from each other. Parallelogram motion is the same. You just need the shiftmate to use Campy shifters/derailler with a Shimano cassette. I assume that your rear wheel has a Shimano freehub, which is the real limiting factor in this case, determining what cassette you can run.
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"c" is not a unit that measures tire width