The scrolling is created automatically based on the viewport option. I see it's set for 8 items in your case, which I believe is too high. I suggest changin it back to the default 4 or lower. The option is located on the Theme Options -> Vertical Results panel: https://i.imgur.com/KxBF5nL.png
The 404 error is most likely not related to the plugin, as the post URLs are requested directly from WordPress itself, meaning it might be defined incorrectly, or there is missing rule in your .htaccess file. Please check the permalink on the page editor for that page, it should be the same as the one in the results list. The only difference to me is, that the permalink for that item starts with /testimonials/ instead of /index.php/, which might indicate that it's set incorrectly in the page editor.
How do I re-create the swiping issue? I tried everything on multiple mobile devices, but I could not see anything strange happening. I have no knowledge of any compatibility issues with Rev slider lately.
It's unfortunately not possible to highlight on the click-through page, as after the redirection the search data is lost, so there is no way of knowing what the search phrase was (unless sending it with a GET request, but that would create an ugly URL for each result)Best,
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