so that splice could be factory.
I set a link for the wiring diagram from the service manual at the top post I made.
Check it out, it will show if that is the case.
IT doesn't look melted rather clamped.

maybe yes, maybe no on the test light.
Those do provide power into the car and back out. The splices go to other circuits to power them up.
But even without them, it would show dead shorts to ground.
If every circuit is dead then you know those were the only damage.
If something lights up then it is time to trace that circuit.

No damage to be done as the test light is the only load and would prevent further damage.