Yea, I have replace the relay, good chance that relay is bad too, because my horn doesn't work either. I have every problem at once lol.Yeah I highly doubt battery is the issue here.
So you checked the starter solenoid wire (the small wire coming from the jeep harness to the starter post) and it had no voltage at all when turning key to crank? If not, then yeah probably an ignition switch issue. Because in that case the Jeep would not be telling the starter to activate.
I'll be curious to see how the ignition switch swap works out. Unless you have a critter eating wires (doubt it), then I bet it will fix the issue.
FYI, starter wire voltage can also be tested at that square plug near the PDC. The ignition wire for the starter runs through that plug and down to the starter.
You also may have a bad starter relay. Have you tried putting the horn relay in its place?
I also did the hammer trick, by hitting the starter while someone cranked. Nothing.
My biggest issue for tomorrow so far seems to be trying to lower the steering column to get to the switch itself.
Edit: What is PDC?