Using a UTM to change a value in Dynamics

When a lead appears in Dynamics and we send it to our sales team, it needs to be noted as an end user for either Company A or Company B. We thought about using a custom utm link for each Company to track which marketo form fills originated from which utm link.

I was hoping the custom utm link for each company would show up as the referral url in the Dynamics lead/contact record, but they are not.

Any suggestions?