Sorry for the late response, I had a few business related things to take care of, and was only able to answer a few tickets quickly.
If I search for something gibberish like “jkaldkj129390123” that would be considered a non-result and trigger the above hook right?
Nope, actually it's the opposite of that, this executes only when there are valid results.
The best solution in this case would be to make an additional change to the plugin ajax handler to allow filtering the results, regardless they exist or not. So, first things first, open up the wp-content\plugins\ajax-search-pro\includes\classes\ajax\class-asp-search.php and scroll to line 74, which should be an empty line, and put this there:
$results = apply_filters('asp_ajax_results', $results, $id, $s, $sd);
Now, this will allow manipulating with the ajax results, regardless of the outcome. Then, your code should translate to something like:Best,
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