I made a new/clean installation with the Astroid demo content package.
If you look at the Blog with sidebar view it works (like in your situation)
When you go to the Blog without sidebar view it keeps spinning.
So i tested and JD Testimonials only seems to work on the blog-view when the search module is published on that page.
I searched in the search override and found 2 lines of code which i added to top of JD Testimonials /tmpl/default.php
This is very helpful. Thanks for the thorough follow ups. I removed it since it was really just copied from the core search module but isn't actually useful for anything but placeholders for IE9 or below.
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