Hi,
Thank you for the details!
You may have an issue with your results page (or something else might be causing an issue there), because when I disable ajax search pro, then go to the default results page, I am getting a completely empty page, the same when the plugin is active: https://i.imgur.com/U0lft3V.png
Check your theme results page code, try removing any customizations or plugins, which may directly affect your theme results page. It should display some elements by default.