This is not KSK via KCG, this is KSK via UBL/MRJ/Pune/DD/MMR. Post Pune-DD-MMR electrificaiton, now it is getting an electric locomotive between Pune-NZM.
GY-KCG route is still not electrified, so KSK via KCG still runs with diesel loco between YPR-KCG and Electric loco between KCG-NZM.