Rear driver-side door will not open.

I know GM door problems are common, but his one seems particularly unique. Previously, the outer door handle stopped opening the door latch, so I took the door panel off and found that the linkage connecting the handle to the latch had come loose from the outer handle. I opened the locking tab connecting the door linkage to the latch, reconnected the door linkage to the handle, and re-closed the tab while positioning the linkage in what felt like the appropriate place to maintain tension on the door handle but also unlock the door. When I was done, the outer door handle, inner door handle and lock knob (at the top of the door panel) all seemed to work as normal; they all moved as normal, and when I closed the door, the inner and outer handles both opened the door. To test it, I must have opened and closed the door two dozen times without issue. However, the one thing I did not try was locking the door remotely (or unlocking it either, of course) while the door was closed.

Here's where the real problem started. After completing the repair above, I went for a short drive during which the doors locked automatically as usual. When I tried to open this door after it had locked, it would not budge. The inner and outer door handles still felt the same as always, so I'm pretty sure they're still connected as usual, and the lock knob at the top of the door panel rises and lowers as you remotely "unlock" or "lock" the door, but even if it's in the unlocked position, the door will not budge. Now I can't even get the panel off to access anything.

Do you have any suggestions? Any idea of what may have caused this problem or how I can even get the door open?

Thanks,
Travis