Have you tried setting up a "Form - Submit" trigger?
![Jennifer_Dungan_0-1686761023887.png Jennifer_Dungan_0-1686761023887.png](https://experienceleaguecommunities.adobe.com/t5/image/serverpage/image-id/58920i4F2C09495E2FD051/image-size/medium?v=v2&px=400)
Add the form identifier in the settings:
![Jennifer_Dungan_1-1686761067757.png Jennifer_Dungan_1-1686761067757.png](https://experienceleaguecommunities.adobe.com/t5/image/serverpage/image-id/58921iD886333E5FD3E70B/image-size/medium?v=v2&px=400)
Now, there is a possibility that the way the form is set up allows allows "submit" actions, then does all validation after the fact to determine IF the user can download the file.... that would complicate matters...
But start with this and see where you get to.