The show was run with the idea of the public voting for the girl they most wanted to star as Nancy in the West End. That was the 'goal' they all worked towards.
Whatever Cameron's (or anyone else's) feelings, Jodie won. Fairly and squarely, and that's all there is to it. I thought I read somewhere that the contract was for 6 months, but could be wrong. If the powers that be find some loop hole to deprive Jodie of her hard-earned prize, then it will be the death knoll for any future show of its kind, and I would imagine the BBC would have something to say about it as well.
Jodie wasn't my overall favourite - Rachel was - but she got the votes. She is the one who the majority want to see, and good luck to her. I hope she acts and sings her socks off when the show opens, and gets rave reviews to beat all rave reviews!