I think I explained it well enough, but basically. He recalled his time at the river (his undead life), not the human life (previous life). He didn't gain old memories, just weakened his memory block.

Fixed! I completly butchered that line.

Fixed! Curious how no one pointed that out.

Corrected, thanks!

I am knowledgeable on how frequencies do work, especially the frequencies of waves, rather than objects. That's why I have used the word oscillation before others. I can understand your disenchantment towards making the mystical acts of magic follow physics. Thanks for your comment!