How to call function after completing ajax call(the ajax call is from third party) which is not in current project on button click event

Question

I am trying to bind search results from Coveo and on click of show more button, there is ajax call to load more facets.

on click of show more arrow button, after ajax call completes(which is getting triggered from Coveo in built JS) I need to call a function after ajax complete method.

Please let me know if there is any other way to load function after ajax complete without using Settimeout. Tried to use AjaxStop but it did not work on click event.

Thanks in advance.