I just know having a working latch will solve lots of problems.
Passat door lock problem.
Common door locking module in this video i show how to deal with the problem buy a vw g.
How gain entry via a vw door that won t open from inside or outside.
When where needed.
Raise support the vehicle safely according to manufacturer jacking supporting positions.
Yes the driver s side is like a master but i m not sure what it controls.
The answer to 1 is yes you have a problem with the lock cylinder.
The two parts metal and plastic are supposed to move as one unit.
The door lock works in only one direction.
If this happens the problem is with the remote.
As you can see in the photo on the lock actuator replacement part for my car door there is a plastic part left and a metal part right.
This issue also indicates a bad lock actuator.
If the unit is rotated anti clockwise then the door lock will be in the locked position.
If you can get you remote working no big deal.
Locks work from the switch but not the remote.
The battery is likely dead and needs to be replaced but the remote s may also need to be reprogrammed to work.