There's no need to paste the whole file, we have a copy
What you want to do is outside the scope of support because the submission forms are not customizable. The code that renders the fields is this line:
<?php echo $CustomFields->makeFormFields($listing_fields,'listing',null,__t("Select",true));?>
So you can try unsetting it from the $listing_fields array. Make sure the keys are the field groups, although I think they are.