There's a difference between "true twin" and "Symmetrical"...and it does confuse a lot of people.
True Twin = the tip and tail are the same height, meaning if you were to take the ski and flip it upside down unmounted and put a level on the base it would be level. The tip and tail sidecut dimensions don't have to be equal for this to occur. I think a lot of people get confused by "true twin" cause the actual phrase is supposed to be "true twin tip"
Symmetrical = is a true twin tip ski that has the same sidecut dimensions for the tip as it does for the tail. Basically, you could cut the ski at the measured center point of the ski and place one on top of the other and they'd match up. Now, usually this also includes the flex of the tip and tail, which is usually referred to as a "true symmetrical twin tip", however, not all skis have the same flex in the tip and tail, but have the same sidecut (like the Volkl Ledge).
That being said...I don't know the answer to "is it a true twin" off the top of my head, but I'm not sure if that's actually what you mean either.