Just to share my most recent window mechanism incident...last Xmas...
...driver's side window on my W124 stopped functioning. It only has the console switch so I don't have the issue of which switch is bad. Figured it was mechanical since I could hear the odd rhythmic clunking noises prior to its demise.
Pulled the panel and the entire mechanism out of the car. Took it to my indie, hoping he had a spare motor he could swap out from one of his donor cars.
We tried a known good motor, and still no budge. Took my motor to a known good mechanism and it worked! Determined that the gearbox mechanism had seized.
No other gearboxes available, so I had to order an new OEM part.
Okay, back to your case:
Do this one at night, it's easier.
with the door open (so the courtesy light is on), hit either the panel switch or the console switch. If the courtesy light dims briefly when you depress either switch, then the fuse, switches, and any ?relays? (etc. are fine). That would point to the mechanism, the motor, or the gearbox.
You would have to take the assembly out and diagnose at this point, in a similar fashion as my indie did...