Removed LP tracking causing SFDC creation issues

We recently removed tracking from a Marketo landing page in order to enable individuals to submit a form as part of a referral program. Person X would submit the form with Person Y's information so Person Y would be created in our system and could be contacted via the referral. We wanted to make sure that Person X wouldn't be cookied and have their web activity appear to be Person Y's web activity. All of that is working just fine - but when Person Y gets created in Marketo, a record is attempting to be created in SFDC and failing. It is saying that their Record Type is invalid. We noticed those leads were being created with a different Record Type ID # than our "normal" leads, so we attempted to hardcode that ID number into the form to "force" the correct value. That also did not work. This is the only form creating this issue, so we have isolated it to the fact that the tracking/cookie information is stripped, but we are unsure of how to resolve it and make sure leads are properly created in SFDC.

For reference, we removed the tracking by:

1. Disabling Munchkin Tracking at template level

2. Disabling prefill for every field at form level

3. Adding <script>  MktoForms2.whenReady(function (form){  form.addHiddenFields({"_mkt_trk":""});  form.onSubmit(function (){     form.vals({"_mkt_trk":""});  });  });  </script>

Any ideas?