A subject line says: "FW: SPOOFED: New submission: Correspondent Partner Request Form"

Is this spam?  

Why would the subject line add "FW: SPOOF:"  ? 

"New submission: Correspondent Partner Request Form" is the subject for your email notification in the form http://www.jotformpro.com/form/50505905241952

This was sent from the notification recipient which is k*******e.g*****r@l*********c.com, this is a form shared with you and you can actually check the email recipients as well as the submissions. 

Unfortunately, I cannot find the submission that was related to that forwarded email, I can only ensure this was due to a submission in your form and it was forwarded from the form's recipient. 

JotForm already protects users against spam submissions, additionally you could add a captcha widget too in order to also avoid spam: How-to-Add-a-CAPTCHA-field

Here're also some guides about set unique submissions in your form: 

How-to-Set-Unique-Submissions-on-a-Form

How-to-set-Form-Limits-Based-on-a-Unique-Question

Hope this helps.