Barracuda not starting after being parked for five years

Try jumping out the ignition switch just to see if it starts. Wire from battery positive to coil positive and then crank. If it starts, then it may be either the ignition switch or the ballast. This is an easy test.

Ran a wire directly from battery + to coil +. Not starting.

No, battery.
11.2 is nearly dead as far as batteries are rated. Perhaps during cranking the the voltage falls to 9 or 9.5.. With the starter taking all the electrons, there will be nothing left over for the coil.

Had my wife work the key while I hung around the battery with the multimeter. During cranking, the battery holds 10 volts.

Is that based on using a spark tester?

Unfortunately, I don't have a spark tester. I held the number 1 wire with the plug in it on the exhaust manifold while my wife cranked the engine. No spark was visible.