I have a motor oil leak coming from the back of the motor
this may help.
How to Replace the Cam Plug (Common Oil Leak) on a Mercedes - Bing video
How to Fix Common Mercedes-Benz Oil Leaks (M112, M113, M272, M273) (fcpeuro.com)
Could be the cam expansion plugs. Replacing them and installing the new ones can be a little tricky.
Depending on the rate of the oil leak…it could be more cost effective to just monitor the oil level and top it off periodically.
A lot of times, a dealer will try and scare you into major engine repairs to fix a small leak. It mainly benefits the dealer’s service department.
Based on your short post, I suspect that you should have it evaluated by a mechanic you trust. If you are unsure of the recommendation, get a second one. It might help your trust level if you have them show you the leak.