If batteries do burn fire must be safely contained and any emission vented overboard. So far the plane has failed on both counts
I'm not so sure that I agree yet with your pass-faill assessments. I'm awaiting the NTSB facts on this.
Just take black boxes for instance. They may look burned all to hell on the ouside but the inside is still readable. The batteries are a mirror image of this. It's the harm they cause that is the measure.
As for venting overboard, that is for under-flight-conditions. It sure seemed to vent, but how much vs how much was it certified for?