They can no huddle because there is a play being shouted out... There wasn't even a HINT of a play being called by Matt Flynn. There's a difference in seeing Peyton Manning no huddle and a first start of his career players' no huddle.
There was no play called, so they didn't know what they were doing. They couldn't line up without knowing the play since it determines how/who they have to block, etc.
Bummer for me is that I'm rooting for Minnesota two weeks in a row!