This thread is resolved. Here is a description of the problem and solution.
Problem: Acf images not displaying on the front end
Solution: The client found a relevant thread and solved the issue https://wpml.org/forums/topic/acf-image-field-returns-an-array-on-regular-page-and-an-id-on-translated-page/ 1) set the _img system field for that custom post and updated the page. 2) batch duplicated all the posts for that custom type.
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