Add Referral Code to Webform on Website

I have 1 webform that appears on several WordPress sites. I need to be able to place an Affiliate Code on each individual form. That way, no matter how the lead gets to me, they are tracked with the code for that page.

Example: I, Austin, am an Affiliate of creates a webpage for me call I need every contact to be assigned to austin as the referral partner regardless of how I get there.

The solution I think will work best is to alter the code of each webform to “force” the appropriate affiliate. However, I don’t know how to write in that string of code.

Can anyone help?