But if 'The Icedragon' is really set in the land of aSoIaF then there must be an awful lot of icedragons around. The Winters grew harder and loger the more Adaras connection with the dragon develloped. For a winter of several years there just have to be more than a few pairs.
The showdown will probably consist out of the Others riding icedracons fighting Dany and two others (whoever they may be), the wolves will grew wings and join in as well and in the end it will turn out that the godswood at Winterfell as Adaras dragon ...