Hi William,
We’re not sure about the script since it’s not part of the theme and cornerstone, we can’t provide any information. The rollback request is not related to the script, it’s only requested so we could see a working copy before the update. The reason for the rollback is because we need a working copy since it’s the live site.
While the requested staging is a cloned or copy of your site where we can investigate and compare it to the working copy. We’re not pointing to whom fault is this, this is just a request and usual procedures of maintaining a site. For example, before you update it, it must be tested in the staging site then migrate it back to the live site once all are fixed. This means your live site will be okay and completely isolated to issues you’re having from the staging site while testing it. Updating a live site while having a ton of customization and configuration may result in this.
And based on previous details you have provided, like layout the fixed itself and missing jQuery, then I can say the issue is the overall site itself including the caches. The theme has no capability to alter jQuery, and the layout remain the same since the templates are the same. Please also note that Wordpress 5.4 update causes too many issues, like doubled custom menus, Gutenberg editor changes that pushes edit with button down. And this is not due to the theme and cornerstone, it’s because of standard/features changes from Wordpress 5.4 and that was released after our recent updates. This is one of the reasons why it needs to be tested first on a separate copy of the main site.
Please request a site restoration to when it’s still working, don’t update anything. Then clone a copy of that restored site and update it, then test everything.
Another question, from what versions you have updated it from? Breaking after an update is normal if there is a large gap between updates, like years resulting to the feature gaps or deprecated features.
Thanks!