This happens at the salvage yards to me... the doors are locked and the battery has been pulld and no keys.
I crawl through to the back and pull off the back door panel. You will most likely break some of the mounts, but you will still be able to remount it after later using the ones that are left.. after you have the panel off, you can reach the mechanism from the inside to unlock it and open it. From there, you will have to figure out exactly what the issue is.. most likely the rod that goes from the key part of the lock has become unattatched from the lock mechanism itself, but that wouldn't affect the lock not being able to be controlled by the electric locks, so you will just have to trace it all and figure it out once you have it open...