The different worlds aren't exact copies by the sound of it. Basically the 14 separate worlds were created back long ago and since then have been developing along their own paths independently. Its highly likely Midgardsormr and Unukalhai are both from reflection worlds originally and we know Unukalhai's world turned out very different to our own.

The WoD were effectively originally WoL from their own world. Since the Ascians are active on all reflection Worlds, there are WoL that rise on all those worlds too. In the case of the WoD they drove the Ascians from their world but the problem is it created an imbalance that threatened to engulf their world. Their actions in 3.4 are a desperate measure, not even to save their world, but to just save the souls of those who dwelt on their world by returning all those souls to the Lifestream of the Source.