Element with more exempted locations than not

I'm guessing I'm abusing the Elements. ;-)

I need three footer widgets on exactly one site page and nowhere else.

As a result, in Elements, I have to opt out a total of 12 pages, post categories, post tags, and custom post types to keep the widgets off the rest of the site.

Surely there's a better way to do this. Obviously, I'm not clued in.

So how do you define a site in the Customizer to include footer widgets on only one page?

I've included a link to the only page on which they're supposed to appear. (And if there's a better way to accomplish the look of that page than by using three footer widgets, I'm all ears.)

For the record: WP, GP/GPP all current.