Can't really find much about the performance, other than many low-quality videos on YouTube and some message board chatter from those who attended.
Word is that the real Dumile showed up and performed, as he did back in May at Soundset in Minnesota.
Here's a couple of pretty good videos I found on YouTube from fans who attended the festival, and a photo of DOOM on stage. (Photo courtesy of dub_g from the ST board)
- Subroc, The Hip Hop Hendrix