I’m unsure whether the darkness rises and light to meet it line is referencing the dyad. Mostly because Snoke thought Kylo’s equal was Luke at first, and he would have no reason to suspect they were a dyad.
Also, the whole “there has been an awakening” is probably not a reference to the dyad either. I believe that is more a reference to the will of the force being put into motion, which all starts with Luke’s map ending up with Rey.