I know this is super long ago, but my dad recorded our duet. It went pretty well, I'd say. A couple false notes here and there (especially at the end) but all in all not catastrophic. First I sing in unison with the girl I was singing with, then I start in the duet part.
Sorry about the terribad video quality. The audio is what matters, right? Also dad started recording a bit late, oh well.
I gotta say, I was so nervous walking up to the stage I almost died. And all of a sudden I really had to pee, and that's what made me actually able to sing. I don't know how, but it did. Bless my bladder.