Ok, the noise is normal - kudos to SoK for taking the time to diagnose it. I only heard it because I had the hood up checking out their work. They listened at the drop off location, even dragging a Tech (Terry) out to hear it. He heard it and couldn't find it, so he took it back to the shop where he worked for a while, finally popping the hood on a 2015 and realizing it did it too. Again let me say I was worried because the brake pedal was also sinking, and when you combine the two symptoms....
Anyway, turns out it had air in the brake system so they bled the brakes - free of charge since they had just done the 30k service. They also washed it up.
All in all, they took care of everything. I filled it up with gas and will monitor usage. I have my radio presets back, seatbelt chime disabled, speed volume set again, and the car didn't forget the MPG correction factor I put in or the tripometer.