Door locks...
 

Ok so here is what is going on...
the driver's side door lock can be unlocked with any key/flathead screwdriver/coin etc... just anything to turn it
the passenger/hatch dosn't unlock/open with anything
the ignition only works with the key that I have for the car, so its the only thing thats actually working as it is supposed to.
this is on an s5 fc, not like it matters... but the anything to unlock it is happening on the back hatch of my s2 fb as well.

Sounds like the locks are worn to hell, replacement time possibly?

Someone had to replace the locks somewhere down the road on my car, and I now have two different keys for doors/hatch and ignition. Seems like they're fairly new too, unlike many worn out locks that FC owners have, no other FC key (or anything) I've come across so far has worked on my doors, whereas my friend has 2 FC's with worn locks and both keys work on both cars.

I was thinking something similar, but i would think that the passenger and hatch would work...
maybe the driver side is just worn to hell, and the others are just jammed up from unuse (but i cant free them... got some nice penetrating lubricant and nothing)
i'm guessing is a big pain in the butt to get every lock and ignition switched out huh? i kinda want to keep it a 1 key car... even if its not that great for safety, its just me :D

Door locks and hatch are super easy, ignition isn't quite as easy. I've removed the ignition key portion one 1 car before and it kind of sucks. Obviously you need to take all the crap around it off but possibly the dash too? I'm not sure, I had the dash out when I did it on this car. Also, it was an s5 and I'm not sure if Mazda did this from the factory to all rx7's or what, but the bolts that hold it into the steering column area had the heads ground off, so you cannot get a socket or anything on them. I had to cut them off and then remove the remainder of the bolts in the ignition once it was out, took a while.

As for why the passenger and hatch are stuck, not sure. If you can find some rx7 friend willing to let you borrow a single lock maybe swap that into the passenger or hatch and see if their key then works. This way you'll know its the lock and not some mechanism or something else I guess.