Hi Chris,
Although when you clicked Show uniquely secured content, the JavaScript was not functioning, actually those users without permissions still could not access the content in Team Site.
Therefore, I would like you to double check if other users without permissions can access that specific folder.
In addition, for this point, I would recommend sending feedback to our operation team. Your timely feedback will help us improve our product and service. Your active participation is highly appreciated.
Regards,
Cherry Wang