Did you make an m3u file listing all of the game's discs, and load that as your game in bizhawk?
If not, open the folder your disc dumps are in (if they're in subfolders, do the folder that the folders are in) and make note of what the filenames are. Hold shift and right click. Select "Open command window here", then type in the following
dir /s /b *.{extension} > exoddus.m3u
where {extension} is the extension of the file that you would load into bizhawk normally (something like ISO or CUE or CCD).
If you ran your dumps through Discohawk, they should have an extension of CCD.
Then open up that m3u file in notepad, and make sure that all discs for your game are accounted for. If discs for other games are in there as well, remove them from the list at this time. Then save your m3u file, and load that directly in BizHawk.
NOTE: If you move your dumps, the m3u file will stop working (as these instructions makes it use absolute paths).
