I don't know that there will only be 1 40 amp fuse. I was hoping to provide you with a link to a PDF of the owner's manual, but the site only goes back as far as 1996. If the linkage moves by hand, the problem likely is not due to ice like I was thinking, but I'm with you, it's odd that the key cylinder doesn't work either. A fuse for the door lock motor would not cause the key cylinder to seize though either.
If you check the fuses and find they are all fine, then you might check the circular multiwire connector in the driver's door jamb. It's fairly common for wires to break at that connector. I could send you or post a copy of the wiring diagram for the 1994 model year which should be very similar to your 1993, but unfortunately it doesn't label the 40A fuse any better than what I described above.
-Rod