Carson ended up with 9% of the vote. I don’t think I ever saw a pre-poll of Carson getting more than 10%. IOW 1% does not a stolen election make.
The election was not stolen but some of Carson’s votes were. Is that okay to steal if the other guy wasn’t winning anyway?
Meaningless. The polls for the Iowa caucus are usually very inaccurate for several of the candidates. Santorum was far down in the polls when he won in 2012. And, Trump was ahead in most all polls this go round, and Cruz second.
The polls have no meaning for the logic you're trying to apply as to how large Carson's vote should have been, or not.