Q: The passenger door is stuck shut. It won't open from the inside or the outside.

About a year ago, my passenger door would sometimes not open after pulling on the door handle of the shut door. Eventually this became permanent. The passenger door won't open from the inside or outside, when I lock and unlock the car, the lock goes up and down and stutters but never seems to fully unlock. I've taken the door panel off from the inside (with the door unable to open that was very difficult). I also removed the passenger seat to have more room to work. There are no large openings after removing the inside door panel. They must've made this thing with a computer and didn't consider human hands or arms to repair things. I can see the outside door latch by rolling the window down and putting a wedge between the window and the door. When I try pushing it down, the door will still not unlatch. I'm assuming the mechanism is stuck in the locked position and pushing down the outside door latch from inside the door panel won't do anything if it thinks it's locked. Any ideas?

My car has 107000 miles.
My car has a manual transmission.