First of all, I rigged up two separate 3.3V power supplies (using a common 5V supply which uses a common 9V supply). I don't know if this is a good idea or not but it's what I decided to do. If anyone sees this as a debacle, let me know :)
Then after some experimenting, I finally got the DAC outputting something similar to the analog source.
Just a black screen:
And here it is with video playing:
The next step is to figure out how to stream this out to dual SD cards at 30 megabytes per second! :)