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
Sort of depends on what the control-data circuit wiring was shorted TO external to the ELT --for example like a 32 vdc bus bar or any power circuit or sneak circuit.
remotely drop a piece of 12 gage or smaller wire across your 12 volt car battery AFTER clearing the area . .