OK, IDK where those vanishing files went, but I uninstalled a second time and reinstalled it again, and it worked this time...
Like the most bizarre magic trick that my computer has performed to this day. No, I will blame Steam this time. That was a magic trick by Steam.
I am NOT asking for an encore, cause that was NOT entertaining.
Moving on, again, Congrats! (I am being sincere, my sarcasm is mostly reserved for weird glitches and clowns (I am adding magicians to the list), but since this is text, I am uncertain if my congrats would be seen as positive when I really am happy for you due to the weird technical issues on my end (no, Steam's end)...)