I almost ALWAYS test stuff under load if possible. That is what WILL show up bad connections/ terminals/ connectors and switches. Using an ohmeter will lead you down the wrong road. I already gave you a pretty good list of what you are up against, but I don't know, in your car, what all there is for the dash lighting. And it could be an abraided wire, touching something it shouldn't.
It could be anything, I won’t know until I talk my son into crawling around for me. We won’t stop until we find it. I would still like to know how to test the switch. If the wire is located it will still blow if the switch is bad