I banged my head for more than 5 hours on this one and finally resolved. Hope this helps someone.
If your PHP page stops executing or gives a fatal error while using exif_read_data() function or any other exif function, there is a fair possibility that exif is not installed – even though it might show in the php.ini file. Follow these instructions to install exif if you are on whm.
1) Navigate to ‘Home »Software »EasyApache 4’ in WHM.
2) Click ‘Customize’ in the top right-hand side of the page.
3) Click ‘PHP Extensions’ on the left-hand menu that appears in this section.
4) In the search bar, type the name of the extension. Then, click the toggle next to the result that appears below. Make sure to install the version that correlates with your installed PHP version (eaphp-XX).
5) Then, in the left-hand menu, click ‘Review’.
6) After reviewing the changes to your packages, click ‘Provision’ near the bottom of this section.
Make sure to install both mbstring and exif module. Enjoy!!