I want to know if its possible to have a email recipient click on unique link which then takes them to a Marketo LP with the UTM and then redirects to my website where I have a Hidden Market form which gets pre-filled with some of the UTM info?
Or alternatively can I by pass the LP altogether and directly send the unique UTM info to my website?
My goal is to be able to populate some fields in my hidden marketo form.
Why wouldn't you link directly to your website in this case?
What you need to be aware of is that submitting a form without user interaction means mail scanners will also submit the form, skewing (possibly drastically) your results.
The form wont be submitted without the user interaction. The idea is I have a refer a friend program. So I want to be able to have current leads (referrer) forward emails(With referrers unique identifier) to their friends to sign up. When the friends clicks on the link it takes them to the sign up (on website) and pre fills certain hidden fields with the referrers unique identifiers. They still need to fill out the website for to sign-up and the hidden form then gets submitted to Marketo with all the details of the new lead.
Based on the above is it possible to do it this way or is there another way?
You don't need JS. A Marketo form can Auto-Fill fields of type Hidden from URL params using just the Form Editor UI options.