Trunk lock problem-Help
 

I have two old Mercedes and a ten year old son. Problem, my son tried to open the trunk in my 300sd with my 560 sl key. Result, trunk locked and key will not go all the way into the cylinder. The slot for the key is locked at an angle and the cylinder is pushed in and I cannot open trunk . Does anyone know anything that can be done short of going to the dealer. I have tried the local locksmiths and they say they can't work on Mercedes. Thanks for any help.