something I just got done doing 5 minutes ago was changing "good" fuses out.....and the window started working.

My 190e, dropped the passenger rear left.....then the rear right.....then the Drivers (which makes life difficult to go thru drive thrus).

I bought fuses, changed fuses, and no help.

For some reason, this morning, I rotated fuses from 7,8,9 and the window started to work again?
All I'm saying is to try the fuses. cheap. rotate them with a known good one.

for getting the panel off, i don't know either. 190e isn't easy. imo.
also the plastic and old trim seems to just crack and fall apart on mine, I'm afraid to touch it almost!

good luck.