Hello Nathan,
I have logged in to your site. I cannot check the child theme’s functions.php file because File Editing is not allowed in your site. Please be aware that by default, the srcset which is displaying in your product images right now were disabled in Pro theme. You may have added a custom PHP function in your child theme to override the theme’s default. If you haven’t added then one of the plugins did. You could try testing for a plugin conflict. You can do this by deactivating all third party plugins, and seeing if the problem remains. If it’s fixed, you’ll know a plugin caused the problem, and you can narrow down which one by reactivating them one at a time.
If nothing is helping, please provide us access to the child theme files or at least post the contents of your Child Theme’s functions.php file.
Best Regards.