I think we have a fundamental disagreement of what The Wake is, not so much what this spell can do. I always think of it like Tel'aran'rhiod from The Wheel of Time, a dream world that is also a dimension of its own.
It does not make sense to me as just a dream world, where nothing there is real, for many reasons. But most importantly, because if we go with the idea nothing there is real Lord of Dreams/Nightmares is a useless ability because nothing it does can affect the real world in any way.
But, if it works like Tel'aran'rhiod, a world separate from our own, a reflection of it really, but just as real if you go there. The dangers there are just as real if you go there in body, and a "Your mind makes it real" thing if you go there in mind/spirit. In this case, while it reflects our world more, our world does reflect it to a lesser degree. From the description I have read, where you are in grave danger if you go there, this way makes more sense to me.
If The Wake is a reality of its own then things that happen there can effect the real world and permanent things done there persist. If it is just a dream world then it is unimportant to our world.