I couldn’t leave well enough alone. I hate having an unsolved tech puzzle. I was up early anyway, this morning, so tinkered a bit more with my mixer, installing Ardour4. Turns out everything works when allowing Ardour4 to direct drive and configuring to just use ALSA. I had no idea ALSA supported firewire but apparently it now does, all channels seem to be present and working. Long story short, I will be recording again no later than this coming weekend.