The generated JavaScript currently calls:
doAjaxPrice(12, 'option-2')
This results in the following console error:
Uncaught ReferenceError: doAjaxPrice is not defined
The function should be called through the J2Commerce namespace instead:
window.J2Commerce.doAjaxPrice(12, 'option-2')
Please update the generated variation handler to use window.J2Commerce.doAjaxPrice() so that product variation selection and price updates work correctly.