1. Was this aircraft held on the runway beyond its calculated Vr?
How could anyone not on the flightdeck possibly know? 
2. How close to the the aircraft's performance and aerodynamics limit was this flight?
The point of ice contamination is that no one knows where "the limit" is.
3. Did the crew actually know their aircraft was contaminated?
How could they not? It's not snowing, so they taxied out with the wings covered in snow.
4. Would the aircraft have flown with the snow on the wings (engine-out)?
See point 2.
5. Is this normal for this airline?
It's not "normal" for ANY airline. That's the point.
Has anybody confirmed the airline yet?
Yes - see the thread in Tech Log.