Can someone help verify my code real quick?

I have the following in my contact form 7

[dynamictext ApplicantSource "CF7_GET key='utm_source'"]
  [dynamictext ApplicantMedium "CF7_GET key='utm_medium'"]

Example URL:
http://smithandkeller.com/awesome-post/?utm_source=facebook&utm_medium=cpc

So if my utm_source is facebook and my utm_medium is cpc such as above, this would grab those values and then in theory I would be able to output them and send in an email via “[ApplicantSource]” and “[ApplicantMedium]” – right?

This is only working part of the time for some reason. I don’t know if it is a server caching issue or something to do with me as admin being logged in – OR maybe I just have a stupid mistake above. Any help would be great.

https://wordpress.org/plugins/contact-form-7-dynamic-text-extension/