Complete electrical failure after a new battery was installed backwards?

The car listed above's engine is a Hemi. A new battery was installed backwards, possibly 10-15 seconds before being disconnected and corrected. Smoke seen from hood briefly. Unable to locate the source. Battery ground cable in trunk very hot, some smoke. Started car, it ran and drove but no blinkers, no front door windows, no radio, no door locks. No warning lights on dash. No blown fuses. Drove home and parked. 2 days later the car was used again for errands with the same issues. After leaving the last stop, the speedometer quit working. While returning home the car shut down completely. It would not start again. No lights, gauges, or sounds when ignition switch was turned on.

Tried jumper cables and three things happened:

First: sparks at battery when attaching cables indicating a "short"
Second: the car started and ran
Third: Shut off immediately when disconnected from jumper cables.

Disconnected the car's cables in the trunk from the battery.
Towed car home, battery voltage was 11.9 and it was placed on charger. Continuity test on positive and negative cables in trunk failed. Continuity test from pos cable to car body panel bolt failed.