just a recommendation.

If I were you I would try to clean every single zone where there is oil, and then try to identify more precisely where oil is coming out before bying any further part.

If you remove the oil filter have a look to the contact surface on the engine crankcase where the gasket is applied in case that surface has been damaged.

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Keep us posted especially if your problem is solved
Present cars:
My car: E-class 420CDI, 2008, W211, V8, 180 000km

Wife's one: C-class 220CDI Sport Coupé, Euro, 2002, W203. 345 000km

Son's one: GLK class, 220CDI, 2009, W204

Sold: E-class 260E, 1988, W124, Wonderfull car sold after 489 000 kilometres of reliable services (engine M103, clutch, brake system and 5 speed manual gear box all original).

Sold: E-class, 320CDI, W210, 2000, 225 000km