So I\'m trying to load dynamic content straight into my checkbox container (group_checkboxes)
First try their own static demo code:
They are using just one fieldset as I mentioned in comments.
If this works, then adjust your script to generate the same markup dynamically and then refresh them
$("input[type='checkbox']").checkboxradio("refresh");
If this will work with their code, you will know that you have error in markup. If not, there is an error with that refresh function. (I know it's not final solution but you have to do a bit of debugging sometimes :)
Edit:
Found similar problems, solved by using Page()
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