WooCommerce AJAX Variation Not Updating Price/Image After Attribute Selection on Custom Theme

Following up on previous discussions regarding WooCommerce product variation display issues, I'm encountering a critical problem where dynamic updates fail entirely.

Specifically, the single-product.js AJAX request isn't correctly returning or processing new price/image data after an attribute selection, often resulting in default values or no change at all on the frontend.

This occurs despite correct attribute setup in the backend and seems isolated to a custom theme environment, ruling out core WooCommerce misconfiguration. Has anyone debugged a similar AJAX variation processing failure in a custom theme context?