Passing UTM values through hidden custom fields?

Hi! I’m trying to pass UTM values through hidden custom fields on my Infusionsoft order form, so that I can track lead source accurately. I’m using a tool called Segmetrics to automatically collect and store the UTM values in Infusionsoft.

This is the order form URL with test UTM values: https://fo104.infusionsoft.app/app/orderForms/-Mental-Model-Club-1-Trial-TEST-FORM?utm_source=Facebook&utm_medium=cpc&utm_campaign=MM07-TEST&utm_content=test

My custom fields are:
utm_source
utm_campaign
utm_medium
utm_content

Is anything wrong with my code, or is there anything else I’m missing?