Hi Michele,
While I haven't tested this - you could arguably add some javascript to add a hidden field to the form, then prefill that hidden field with a specific value (e.g. campaign id or elqCampaignId). I can confirm that the component does support Javascript because we use custom javascript to validate that the end user types in an email address in the interstitial page (sample JS below).
We put this JS in the "HTML after the form" field.
<script type="text/javascript">
$(document).ready(function () { $("#RedirectForm").bind("submit",function(){ if($("input[name='phone']").val() == "" || $("input[name='email']").val() == ""){ alert("All fields are required."); return false; } return true; });
});</script>