Not sure if anybody is actually reading this, but here's an update of the little progress I've made.

I rechecked all the fuses in both fuse boxes with a multimeter and they're definitely all still good. I also used a test light on all the fuses and everything is getting power except the the PK/LP RH and PK/LP LH fuses in the engine compartment. I pulled the park lamp relay and confirmed it does close when voltage is applied and the circuit has continuity after that. However, I'm not positive that the relay is closing when it's actually in the car. I pulled out the IP dimmer switch and tested for power but got nothing. I was testing through the front, though, where the blades of the dimmer plug in. Do I need to test the actual wires themselves? I tested the power pin for continuity the same way and that worked, so is there no power getting to the dimmer? Trying to figure out where to check next...