Hold up man...i got an 190E with M104 3.0L 24V engine under my hood...I do rallyCross , Rally Sprint , Drag and mountain rally...And i got a 4 speed gearbox and a 5 speed gearbox both are manual...why the hell you would drive a automatic gearbox Merc on a rally?
Automatics are heavier and stick shift isn't that hard to find in a 190 here if you look. I have 3 with 3 different styles of manual transmission by Mercedes. Wanna buy one?
The rally car doesn't have a whisker on the steering wheel for the wiper like you normally would, so I guess he just installed an on/off switch for it on the dash somewhere. So when he cuts out the power for the wiper it stops on whatever position it is in the moment you cut off the power. You could do that with your own regular car too with shutting off ignition mid-wipe.