How do I turn off the child safety locks in the rear so people can just open the locked door by pulling on the handle to get out.

 

on W220 - on your instrument cluster scroll to the menu that says something like "all setting can be erased pushing R", then press either up or down buton on your steering wheel and find option that tells automatic door locks - on or off

 

You should check the door around the lock.
I don't remenber exactly but either with the key extension (metalic) or just with the finger you can choose that the door can be open from inside or not.