Zadar, if these marks are. . .
just 'brownish' color, they are not burn marks, but are a bit of silver oxide. Typically you will see this toward the top of the pin.
This is standard thing that happens and can cause an intermittent contact: this will clean up with use of steel wool. You can also clean the inside of the mating female pin and that may just fix the problem.
In your case this had nothing to do with what happened. Just info for next time.
Regards . . . . JimF
'94 S500 Cpe
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