dorset culture

Despite the fact that they managed to populate the various islands of the Arctic archipelago(albeit quite sparsely) and even reach Greenland, they never managed reach Iceland before the Norse started settling there. This could be attributed to a variety of factors, but this is alternate history...

The Dorset were the pre Inuit inhabitants of northern North America, could they succesfully colonise Iceland before the Norse? What effects would this have on history? How would they react to the Norse and how would the Norse react to them?