That is interesting.
the fact that you have voltage in run says you have continuity.
if you unplug the wires from the ballast, you should see that voltage go away in run.
The fact that you tried 2 switches doesn't mean they are both good.
have you checked for continuity in the switch itself?
have someone hold it in start and see if you have a circuit from power to ign 2.
since they both act the same, you don't even need to pull the one in the truck.