NEED HELP with B15 sentra!

[Hussain]

my wife has a B15 sentra, I think it's a GXE. her driver side door will no longer open from the inside. from the outside the door opens fine but from the inside it wont. sort of like having child safety lock on the driver door lol so me and my father in-law tried to fix it and WOW, this thing is a PIA to work with. so when you take off the door panel and a couple other things, this is what it looks like



so as you can see, the area near the latch is blocked off by a sheet of metal. I tried to see if I could unscrew it but its all welded together. so then I tried to stick my head in the little spot to see if I could see anything from inside the door and this is what I saw



so this black bar that goes up to the top of the window is in front of what I need to try and fix.

so my question is, has anyone else had this problem before? and if so, how did you fix it? I'd appreciate a response ASAP... my father in-law wants to take a saw to the door tomorrow and cut part of it off to try make room to work on it.