I don't know the specific diploma standards, but I will say that Angela Hewitt's numerous Bach performances has converted me into a "fan" of doing the repeats. Yes, I know she's far from the only recording artist to perform this way (I don't know if anyone records without the repeats), but that's probably the main thing I learned from her recordings of Bach.
She always has something interesting to "say" in the repeats.
The dance movements in the Cm partita, though, are already pretty long, IIRC, but I might just be thinking of the Sinfonia (beginning "dance").
I still say you should perform the repeats, and give yourself the chance to demonstrate creativity and adaptation in different ways of the music.
And, a bit more cynically, in performance, it's almost like giving yourself a "do-over" if you're not happy with the first repeat.
I can't think of a reason to not perform the repeats. Especially when it happens to be very good music, as in this partita. But, I really don't know the specific standards of the judges.