but as far as this incident is concerned, the ships wiring could be a bit of a red herring.
It always has been.
The only wiring to and from the ELT is control/data wiring which carrys miliamps of current and is not directly connected to the battery.
If any of these wires were incorrectly connected or short circuit it would cause logic problems for the ELT controller chip but it wouldn't catch on fire.