Okay, I thought I had figured this out by editing the 1st and 3rd columns of the luCategories view to use @Unique in front of Categories. Nope, did not work.
So, my workaround is an agent that refreshes all Wiki page documents. But, this is poor workaround since the modified date gets changed; still, it's better than duplicate categories.
BTW, I have removed the @Lowercase everywhere I could in front of the Categories field in various views and such and now I can get proper case categories.
Be happy to share the agent if anyone is interested.