Only reason its 'not for DSG' is that normally the DSG pedal is wider.
Inreality a manual dead pedal will fit a DSG car, but a DSG dead pedal wouldn't work for a manual car.
As it happens I'm getting a custom might up one for mine. I could get the larger DSG version of that, but I prefer the narrower manual one I have at the moment. Give me more room between the brake pedal and dead pedal if I needed to stretch my leg out fully on a long drive.
I prefer the extra space too. No need for a huge rest plate and looks nicer in my opinion. Very happy with the quality of this one that I got and it fit perfectly.