Well, in my opinion Aslan is a God, seeing as he did create Narnia and therefore to Narnia, he is the divine creator.
I don't remember anything that refurred to a dream, but then again, since I was so young, the last few books didn't have much of a grip on me, if it was mentioned then ... I don't think it was ...
Interesting theory though.
Well Edmund sat there and listened to what the Beavers spoke about then left and told the Witch, to get some turkish delight.
He did seem to be a traitor as he sold out the plans and his own brother and sisters, so to speak.
However I think Aslan was able to forgive him, he was young, foolish and as you said it wasn't his fault. A young boy wouldn't know how to analyse a situation like that, especially in such unfamillar surroundings.
Yes, tHat's what I thought... Or maybe I would never return. Narnia would be such a beautiful place to live and to die.