Trying to edit the Reviews page with Elementor, you'll notice that each tab item contains an Elementor template:
The easiest way to access these templates is to mouse-hover the "Edit with Elementor" link on the top Toolbar, locate and click on the Reviews Page - Google and Reviews Page - Yelp sections:
Clicking on it will redirect you to the template's content:
You can also access the templates from Dashboard > Templates > Saved Templates:
Make your customizations, following this guide: Guide to Vamtam Elementor Builder