Show success message automatically once form is submitted

I have a resources collection in my site where I’d like to make some attachment resources available. I’d like users to complete a form to be able to download the attachment resources. But, I only want to require the user to complete the form once, then all resources essentially should be unlocked. I’ve figured out how to hide the form after it’s been submitted once using custom code in the footer. I’ve also gotten the attachment embedded in the success message section. But what I need is for the success message section to show for all once the form has been submitted once by the user. Does anyone know how I can skip to the success message of the form always if the form has been detected as submitted?

Here is the custom code I’m using:


Here is my site Read-Only: GraceBlocks Resource: Introduction to Blocks