The prophecy says a "blade" of light, not a "sword" of light. Foretellings may be abstract, but I don't think that anyone would say an angreal in the shape of a man holding a crystal aloft would constitute a blade, no matter the metaphorical significance of it. The light that people saw from miles away was from the break in the clouds directly above him, not from the CK itself, and we are only sure that it would be seen as far away at the White Tower.

The 3 voices in his head, main/dark Rand, innocent Rand, and LTT could be 3 becoming one, but I think the fact that this moment is already spoken of in prophecy is a good indication otherwise. We don't have 2 wholly different prophecies about the same moment anywhere else in the series.

"At the end of time, when the many become one, the last storm shall gather it's angry winds to destroy a land already dying. And at it's center, the blind man shall stand upon his own grave. There he shall see again, and weep for what has been wrought."