How do I add the date to the cite

Step-by-step guide

You can use the filter `testimonials_widget_cite_html` to add the testimonial date to the cite.

You can add the  following sample code to your theme's `functions.php` file to do so, only on a particular page. Do note that the code like `16507 != get_the_ID` is meant to prevent this function from running on that page. Don't blatantly copy and paste expecting things to work if you don't understand the code.