Actually, the picture of the vehicle didn't have skulls, but the Afrika Corps insignia and was taken in Oman, not Afghanistan.
There was another incident where some German troops, but not KSK, made some obscene pictures with human skulls found near Kabul. Some of them were later court-martialed, IIRC.
The low profile may instead stem from accusations of abuse at the hands of the KSK of a German national captured in Pakistan and interrogated in Kandahar.
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