The problem is that we have no idea where the problem is occurring.
It could be the burning, but it could also very well be the way you're attempting to create the image in the first place.
The standard, untouched, DiscJuggler settings are the ones needed to burn most DC homebrew properly. If you've changed them at any point, you should change them back.
Also, why don't you start a new thread detailing the steps you took in preparing the DreamSNES disc contents, ie - roms, roms.lst, plainfiles, plainfiles version, version of BootDreams being used.
Two personal notes:
1.) I'd use Alcohol 120, it's better for DC images.
2.) If you have a swap disc, just burn a separate roms disc with the correct layout, and it'll work.