Create a page template with No Footer

The correct way to load footer-none.php is:

get_footer("none");

Anyway, I think it can be better to use wp_footer() (required function on any frontend page) directly in the page template file so you don’t need to load any empty footer template (assuming you load all required HTML tags in the page template, for example closing body and html).

If you are going to use the custom footer template in more than one page, then it would be better to maintain a separated custom footer template. It is up to your preference.