Are you saying that the power locks are opening the other three doors, but not the drivers door, and that you need to manually insert the key into the lock on the drivers door to unlock it? If that's the case, the electronic actuator in the door that controls the power locks may be dead. Looking around on the internet yields that specific part being between $200 and almost $800. Seems like a ripoff for a simple part like that, but I found this one on Amazon in the mid-$200 range: Door Lock Actuator
Hopefully this is what you are looking for! Good luck if you do decide to attempt the repair!