There's probably still too many different DAC chips to consider at this stage. I think the last VGM2MID beta build is still largely incomplete with YM2151 support, let alone the various DAC chips currently supported in the VGM spec.
You're probably going to either hang tight, or learn how to decode registers from a VGM using said DAC chip to useful MIDI commands, or otherwise stick to old-fashioned "mute everything else but the DAC channel(s)" and do it by ear, or visually with a sound editor of your choice.
