As Steve said, I never see coolant leak from this area. I see it more often from the o-ring that is sealing the heater pipe (near the oil filter) to the head. The thing will leak there and run down the head where it drips off.
Good luck. I think a $2.00 o-ring and a hour labor will fix the problem.
ASE CERTIFIED MASTER AUTO TECHNICIAN
MERCEDES SPECIALIST 11 YRS