I really do not understand all of this. Yes he left us but if somebody offered to pay you a lot more than you are earning now and give you the chance to work for whoever is the seen as one the best company's in your particular industry wouldn't you give it a go!!! Course you would. Liar if you say no.
Then if it all went tits up and you felt that you had made a big mistake, would you be really chuffed if your previous employer got in touch and said hey come on back. Course you would. In fact you would be very grateful and even more determined to repay that and be even more loyal than you were before.
We loved him when he was with us and we will love him again. He gives his all (unlike some that we have ie Bently) and he scores goals.
Get over it and give him and the team the support they need. The last thing the team needs now is bickering about who should be Captain or who should be first down the tunnel for Christs sake. If any of the team are "upset" by him coming back or being made Captain and they throw their Rolex's out of their Bently convertables then they can f£$k off as far as I am concerned as they obviously don't really care about who they play for.