I am seeking advice on the best way to:
Provide separate secure URLs for each industry (sub-segment type) for lead to access gated content
Leads click on secure URL via social channel (eg: facebook)
Lead views secure dynamic landing page (relevant to industry segment) (Serve up URL with as:
Lead completes form to access guide
Receives email with content
When you add a field to your field with type Hidden, you may also choose where to AutoFill the value from. In this case, you want to fill from "URL Parameter." This is all in the docs and in a large number of Community threads.
You can also define the follow-up page based on the values in the form.