Thanks for the update. At least you've found the root of the problem.
I see their documentation regarding this here:
Understand Managed WordPress security: https://godaddy.com/help/understand-man … rity-40956

I hope GoDaddy is willing and able to relax this security measure for your wp-content/plugins/wp-juicebox directory as it breaks the functionality of WP-Juicebox.

It sounds like this applies only to their Managed WordPress platform and not to a regular WordPress site hosted on their web server.
Maybe you could download and install WordPress on your web space yourself and then migrate your Managed WordPress site to the regular WordPress site following GoDaddy's own instructions here:
Move a Managed WordPress site to an unmanaged WordPress account: https://godaddy.com/help/move-a-managed … ount-19798

Otherwise, you could manually embed your Juicebox galleries into your WordPress posts using the baseUrl method of embedding documented here.
Here's an example:

Step #1
Create a gallery with JuiceboxBuilder-Pro (on your computer) and save it to a new empty folder named "my_gallery_folder".

Step#2
Upload the entire gallery folder (not just the contents) to the root directory of your web space (using an FTP program such as Filezilla: https://filezilla-project.org/.)
The root directory will likely be named something like 'public_html' or 'htdocs' (depending on your web server).

Step #3
Create a new 'Custom HTML' Gutenberg block in your WordPress post.
Click the '+' symbol in your WordPress post to create a new Gutenberg block. Scroll down to the 'Formatting' section and select the 'Custom HTML' block type.
Now paste the following embedding code into the 'Custom HTML' block.

<!--START JUICEBOX EMBED-->
<script src="/my_gallery_folder/jbcore/juicebox.js"></script>
<script>
    new juicebox({
        baseUrl: "/my_gallery_folder/",
        containerId: "juicebox-container",
        galleryWidth: "100%",
        galleryHeight: "600",
        backgroundColor: "#222222"
    });
</script>
<div id="juicebox-container"></div>
<!--END JUICEBOX EMBED-->

The leading slashes in the paths above denote your root directory so the code above will work without modification as long as your gallery folder is named "my_gallery_folder" and has been uploaded to your root directory.

You can, of course, name your gallery folder anything you like but you'll need to make sure that the correct gallery folder name is used in the two paths within the embedding code.
Also, you can upload your gallery folder to anywhere on your web server as long as the two paths within the embedding code (the path to the 'juicebox.js' file and the baseUrl entry itself, pointing towards the gallery folder) are correct.
I just used "my_gallery_folder" as the gallery folder name for this example and suggest that you upload the gallery folder to your root directory for convenience.

That's all you need to do to embed a Juicebox-Pro gallery into a WordPress post and you can replicate this process as many times as you like.
Of course, for subsequent galleries, you'll need to change the name of the gallery folder (so that each gallery folder has a unique name) and change the two instances of the folder name in the embedding code, but that's all.

I hope this helps.